{"code":0,"msg":"success","data":[[{"head_title":"填空题","questions":[{"question_id":"6976013","question_type":"4","question_channel_type":"4","is_explain":"1","is_on_sale":"1","question_status":"2","chid":"3","xd":"2","parent_id":"0","is_objective":"0","difficult_index":"1","master_level":"2","exam_type":"2","evaluated":"0","region_ids":"25","grade_id":"9","question_source":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷","mode":"2","title":"已知x=-1是一元二次方程ax2+bx-2=0的一个根,那么b-a的值等于.","kid_num":"2","paperid":"786101","save_num":"52","oldqid":"0","explain_sort_need":"0","paper":{"pid":"786101","title":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷"},"extra_file":"","question_text":"已知x=-1是一元二次方程ax2+bx-2=0的一个根,那么b-a的值等于.","options":"","sub_explanation":[""],"knowledge":null,"category":null,"is_collect":false,"done":false,"myanswer":{"1":""},"score":{"score":0},"sort":1,"sort2":1,"is_use":0},{"question_id":"6976015","question_type":"4","question_channel_type":"4","is_explain":"1","is_on_sale":"1","question_status":"2","chid":"3","xd":"2","parent_id":"0","is_objective":"1","difficult_index":"3","master_level":"4","exam_type":"2","evaluated":"0","region_ids":"25","grade_id":"9","question_source":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷","mode":"2","title":"在一个不透明的盒子中装有12个白球,若干个黄球,它们除了颜色不同外,其余均相同.若从中随机摸出一个白球的概率是 13 ,则黄球的个数是.","kid_num":"2","paperid":"786101","save_num":"23","oldqid":"0","explain_sort_need":"0","paper":{"pid":"786101","title":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷"},"extra_file":"","question_text":"在一个不透明的盒子中装有12个白球,若干个黄球,它们除了颜色不同外,其余均相同.若从中随机摸出一个白球的概率是 ,则黄球的个数是.
","options":"","sub_explanation":[""],"knowledge":null,"category":null,"is_collect":false,"done":false,"myanswer":{"1":""},"score":{"score":0},"sort":2,"sort2":2,"is_use":0},{"question_id":"6976017","question_type":"4","question_channel_type":"4","is_explain":"1","is_on_sale":"1","question_status":"2","chid":"3","xd":"2","parent_id":"0","is_objective":"1","difficult_index":"1","master_level":"2","exam_type":"2","evaluated":"0","region_ids":"25","grade_id":"9","question_source":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷","mode":"2","title":"如图,在圆O中,若 ∠ ABC=50 ∘ ,则 ∠ AOC= ∘ .","kid_num":"1","paperid":"786101","save_num":"82","oldqid":"0","explain_sort_need":"0","paper":{"pid":"786101","title":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷"},"extra_file":"","question_text":"如图,在圆O中,若 ABC=50 ,则 AOC= .
x | -2 | -1 | 0 | 1 | 2 |
y | 0 | 4 | 6 | 6 | 4 |
从上表可知,下列说法中正确的是.(填写序号)
① 抛物线与x轴的一个交点为(3,0);②函数y=ax2+bx+c的最大值为6;
② 抛物线的对称轴是直线 ; ④在对称轴左侧,y随x增大而增大.
","options":"","sub_explanation":null,"knowledge":null,"category":null,"is_collect":false,"done":false,"myanswer":{"1":""},"score":{"score":0},"sort":6,"sort2":6,"is_use":0}],"scores":[],"sum_score":0,"question_num":6},{"head_title":"选择题","questions":[{"question_id":"3581315","question_type":"1","question_channel_type":"1","is_explain":"1","is_on_sale":"1","question_status":"2","chid":"3","xd":"2","parent_id":"0","is_objective":"1","difficult_index":"3","master_level":"1","exam_type":"2","evaluated":"0","region_ids":"17","grade_id":"9","question_source":"2016-2017学年湖北省黄石市阳新县富池片区九年级上学期期中数学试卷","mode":"2","title":"下列图形中,是中心对称图形但不是轴对称图形的是( )","kid_num":"0","paperid":"151759","save_num":"17","oldqid":"0","explain_sort_need":"0","paper":{"pid":"151759","title":"2016-2017学年湖北省黄石市阳新县富池片区九年级上学期期中数学试卷"},"extra_file":"","question_text":"下列图形中,是中心对称图形但不是轴对称图形的是( )","options":{"A":" ","B":" ","C":" ","D":""},"sub_explanation":null,"knowledge":null,"category":null,"is_collect":false,"done":false,"myanswer":"","score":{"score":0},"sort":7,"sort2":7,"is_use":0},{"question_id":"6976027","question_type":"1","question_channel_type":"1","is_explain":"1","is_on_sale":"1","question_status":"2","chid":"3","xd":"2","parent_id":"0","is_objective":"1","difficult_index":"1","master_level":"2","exam_type":"2","evaluated":"0","region_ids":"25","grade_id":"9","question_source":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷","mode":"2","title":"二次函数y=x2+bx+c,经过配方可化为y=(x-1)2+2,则b,c的值分别为( )","kid_num":"1","paperid":"786101","save_num":"107","oldqid":"0","explain_sort_need":"0","paper":{"pid":"786101","title":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷"},"extra_file":"","question_text":"二次函数y=x2+bx+c,经过配方可化为y=(x-1)2+2,则b,c的值分别为( )
","options":{"A":"5,-1","B":"-2,3","C":"-2,-3","D":"2,3"},"sub_explanation":null,"knowledge":null,"category":null,"is_collect":false,"done":false,"myanswer":"","score":{"score":0},"sort":8,"sort2":8,"is_use":0},{"question_id":"6976029","question_type":"1","question_channel_type":"1","is_explain":"1","is_on_sale":"1","question_status":"2","chid":"3","xd":"2","parent_id":"0","is_objective":"1","difficult_index":"1","master_level":"2","exam_type":"2","evaluated":"0","region_ids":"25","grade_id":"9","question_source":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷","mode":"2","title":"一个不透明的袋子中装有5个黑球和3个白球,这些球的大小、质地完全相同,随机从袋子中摸出4个球,则下列事件是必然事件的是( )","kid_num":"1","paperid":"786101","save_num":"19","oldqid":"0","explain_sort_need":"0","paper":{"pid":"786101","title":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷"},"extra_file":"","question_text":"一个不透明的袋子中装有5个黑球和3个白球,这些球的大小、质地完全相同,随机从袋子中摸出4个球,则下列事件是必然事件的是( )
","options":{"A":"摸出的4个球中至少有一个球是白球","B":"摸出的4个球中至少有两个球是白球","C":"摸出的4个球中至少有两个球是黑球","D":"摸出的4个球中至少有一个球是黑球"},"sub_explanation":null,"knowledge":null,"category":null,"is_collect":false,"done":false,"myanswer":"","score":{"score":0},"sort":9,"sort2":9,"is_use":0},{"question_id":"6976031","question_type":"1","question_channel_type":"1","is_explain":"1","is_on_sale":"1","question_status":"2","chid":"3","xd":"2","parent_id":"0","is_objective":"1","difficult_index":"1","master_level":"2","exam_type":"2","evaluated":"0","region_ids":"25","grade_id":"9","question_source":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷","mode":"2","title":"如图,AB是圆0的直径,弦CD ⊥ AB于点E,则下列结论正确的是( )","kid_num":"1","paperid":"786101","save_num":"54","oldqid":"0","explain_sort_need":"0","paper":{"pid":"786101","title":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷"},"extra_file":"","question_text":"如图,AB是圆0的直径,弦CD AB于点E,则下列结论正确的是( )
如图,将等边△ABC绕点C顺时针旋转120°得到△EDC,连接AD,BD.则下列结论:
①AC=AD;②BD⊥AC;③四边形ACED是菱形.
其中正确的个数是( )
,
,
","answer_json":["解: ,,
,
"],"explanation":"","pic_answer":"0","pic_explanation":"0","sub_explanation":null,"knowledge":null,"category":null,"done":false,"myanswer":"","sort2":1},{"question_id":"45067497","qsn_id":null,"question_type":"5","question_channel_type":"0","is_explain":"0","is_on_sale":"0","question_status":"0","question_tags":"","chid":"3","xd":"2","create_by":"1348058075_O54gFl","create_uid":"7693066","create_date":"2018-02-28 09:05:09","update_by":"","update_uid":"0","update_date":"2021-07-01 19:54:04","update_reason":"","audit_by":"","audit_uid":"0","audit_date":null,"audit2_by":"","audit2_uid":"0","audit2_date":null,"opinion":null,"parent_id":"6976041","sort":16,"is_objective":"0","difficult_index":"0","master_level":"0","exam_type":"0","evaluated":"0","region_ids":"","grade_id":"0","question_source":"","mode":"2","is_delete":"0","md5sum":"","title":"","kid_num":"0","paperid":"0","save_num":"0","oldqid":"0","explain_sort_need":"0","paper":null,"extra_file":"","question_text":"","options":"","answer":"解: , ,,
,
,
","answer_json":["解: , ,,
,
,
"],"explanation":"","pic_answer":"0","pic_explanation":"0","sub_explanation":null,"knowledge":null,"category":null,"done":false,"myanswer":"","sort2":2}],"knowledge":null,"category":null,"is_collect":false,"done":false,"myanswer":"","score":{"score":0,"subScore":[0,0]},"sort":15,"sort2":15,"is_use":0},{"question_id":"6976047","question_type":"5","question_channel_type":"6","is_explain":"1","is_on_sale":"1","question_status":"2","chid":"3","xd":"2","parent_id":"0","is_objective":"0","difficult_index":"3","master_level":"4","exam_type":"2","evaluated":"0","region_ids":"25","grade_id":"9","question_source":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷","mode":"2","title":"如图,已知 △ ABC,以AB为直径的圆O分别交AC于D,交BC于E,连接ED,若ED=EC.求证:AB=AC.","kid_num":"3","paperid":"786101","save_num":"59","oldqid":"0","explain_sort_need":"0","paper":{"pid":"786101","title":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷"},"extra_file":"","question_text":"如图,已知 ABC,以AB为直径的圆O分别交AC于D,交BC于E,连接ED,若ED=EC.求证:AB=AC.
","options":"","sub_explanation":null,"knowledge":null,"category":null,"is_collect":false,"done":false,"myanswer":"","score":{"score":0},"sort":17,"sort2":16,"is_use":0},{"question_id":"6976049","question_type":"5","question_channel_type":"25","is_explain":"1","is_on_sale":"1","question_status":"2","chid":"3","xd":"2","parent_id":"0","is_objective":"0","difficult_index":"3","master_level":"4","exam_type":"2","evaluated":"0","region_ids":"25","grade_id":"9","question_source":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷","mode":"2","title":"如图,按要求画出图形:①以A点为旋转中心,将 △ ABC绕点A顺时针旋转90 ∘ 得 △ AB<sub>1</sub>C<sub>1</sub>,画出 △ AB<sub>1...","kid_num":"1","paperid":"786101","save_num":"17","oldqid":"0","explain_sort_need":"0","paper":{"pid":"786101","title":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷"},"extra_file":"","question_text":"如图,按要求画出图形:①以A点为旋转中心,将 ABC绕点A顺时针旋转90 得 AB1C1 , 画出 AB1C1;
②作出 ABC关于坐标原点O成中心对称的△A2B2C2 .
","options":"","sub_explanation":null,"knowledge":null,"category":null,"is_collect":false,"done":false,"myanswer":"","score":{"score":0},"sort":18,"sort2":17,"is_use":0},{"question_id":"6976051","question_type":"7","question_channel_type":"28","is_explain":"1","is_on_sale":"1","question_status":"2","chid":"3","xd":"2","parent_id":"0","is_objective":"0","difficult_index":"3","master_level":"4","exam_type":"2","evaluated":"0","region_ids":"25","grade_id":"9","question_source":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷","mode":"2","title":"在一个不透明的布袋中有2个红球和3个黑球,它们只有颜色上的区别.","kid_num":"2","paperid":"786101","save_num":"11","oldqid":"0","explain_sort_need":"0","paper":{"pid":"786101","title":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷"},"extra_file":"","question_text":"在一个不透明的布袋中有2个红球和3个黑球,它们只有颜色上的区别.","options":"","sub_explanation":null,"list":[{"question_id":"45067477","qsn_id":null,"question_type":"5","question_channel_type":"0","is_explain":"0","is_on_sale":"0","question_status":"0","question_tags":"","chid":"3","xd":"2","create_by":"1348058075_O54gFl","create_uid":"7693066","create_date":"2018-02-28 09:05:09","update_by":"","update_uid":"0","update_date":"2021-07-01 19:54:04","update_reason":"","audit_by":"","audit_uid":"0","audit_date":null,"audit2_by":"","audit2_uid":"0","audit2_date":null,"opinion":null,"parent_id":"6976051","sort":19,"is_objective":"0","difficult_index":"0","master_level":"0","exam_type":"0","evaluated":"0","region_ids":"","grade_id":"0","question_source":"","mode":"2","is_delete":"0","md5sum":"","title":"","kid_num":"0","paperid":"0","save_num":"0","oldqid":"0","explain_sort_need":"0","paper":null,"extra_file":"","question_text":"从布袋中随机摸出一个球,求摸出红球的概率;","options":"","answer":"解: ","answer_json":["解: "],"explanation":"","pic_answer":"0","pic_explanation":"0","sub_explanation":null,"knowledge":null,"category":null,"done":false,"myanswer":"","sort2":1},{"question_id":"45067479","qsn_id":null,"question_type":"5","question_channel_type":"0","is_explain":"0","is_on_sale":"0","question_status":"0","question_tags":"","chid":"3","xd":"2","create_by":"1348058075_O54gFl","create_uid":"7693066","create_date":"2018-02-28 09:05:09","update_by":"","update_uid":"0","update_date":"2021-07-01 19:54:04","update_reason":"","audit_by":"","audit_uid":"0","audit_date":null,"audit2_by":"","audit2_uid":"0","audit2_date":null,"opinion":null,"parent_id":"6976051","sort":20,"is_objective":"0","difficult_index":"0","master_level":"0","exam_type":"0","evaluated":"0","region_ids":"","grade_id":"0","question_source":"","mode":"2","is_delete":"0","md5sum":"","title":"","kid_num":"0","paperid":"0","save_num":"0","oldqid":"0","explain_sort_need":"0","paper":null,"extra_file":"","question_text":"现从布袋中取出一个红球和一个黑球,放入另一个不透明的空布袋中,甲乙两人约定做如下游戏:两人分别从这两个布袋中各随机摸出一个小球,若颜色相同,则甲获胜;若颜色不同,则乙获胜.请用树状图(或列表)的方法表示游戏所有可能的结果,并用概率知识说明这个游戏是否公平?","options":"","answer":"解:列表法:红 | 黑 | 黑 | |
红 | (红,红) | (红,黑) | (红,黑) |
黑 | (黑,红) | (黑,黑) | (黑,黑) |
由表可知,两次摸球有6种等可能情况,其中颜色相同的结果有3次,颜色不同的结果有3次,
∵ ∴这个游戏是公平的","answer_json":["解:列表法:红 | 黑 | 黑 | |
红 | (红,红) | (红,黑) | (红,黑) |
黑 | (黑,红) | (黑,黑) | (黑,黑) |
由表可知,两次摸球有6种等可能情况,其中颜色相同的结果有3次,颜色不同的结果有3次,
∵ ∴这个游戏是公平的"],"explanation":"","pic_answer":"0","pic_explanation":"0","sub_explanation":null,"knowledge":null,"category":null,"done":false,"myanswer":"","sort2":2}],"knowledge":null,"category":null,"is_collect":false,"done":false,"myanswer":"","score":{"score":0,"subScore":[0,0]},"sort":19,"sort2":18,"is_use":0},{"question_id":"6976057","question_type":"7","question_channel_type":"28","is_explain":"1","is_on_sale":"1","question_status":"2","chid":"3","xd":"2","parent_id":"0","is_objective":"0","difficult_index":"3","master_level":"4","exam_type":"2","evaluated":"0","region_ids":"25","grade_id":"9","question_source":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷","mode":"2","title":"如图,AB为圆O的直径,PD切圆O于点C,交AB的延长线于点D,且 ∠ D=2 ∠ CAD.","kid_num":"4","paperid":"786101","save_num":"14","oldqid":"0","explain_sort_need":"0","paper":{"pid":"786101","title":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷"},"extra_file":"","question_text":"如图,AB为圆O的直径,PD切圆O于点C,交AB的延长线于点D,且 D=2 CAD.","options":"","sub_explanation":null,"list":[{"question_id":"33289351","qsn_id":null,"question_type":"5","question_channel_type":"0","is_explain":"0","is_on_sale":"0","question_status":"0","question_tags":"","chid":"3","xd":"2","create_by":"1348058075_O54gFl","create_uid":"7693066","create_date":"2018-02-28 09:05:09","update_by":"","update_uid":"0","update_date":"2024-01-24 07:08:31","update_reason":"","audit_by":"","audit_uid":"0","audit_date":null,"audit2_by":"","audit2_uid":"0","audit2_date":null,"opinion":null,"parent_id":"6976057","sort":21,"is_objective":"0","difficult_index":"0","master_level":"0","exam_type":"0","evaluated":"0","region_ids":"","grade_id":"0","question_source":"","mode":"2","is_delete":"0","md5sum":"","title":"","kid_num":"0","paperid":"0","save_num":"0","oldqid":"0","explain_sort_need":"0","paper":null,"extra_file":"","question_text":"求 D的度数;","options":"","answer":"解:∵ 和 分别是弧 所对的圆心角和圆周角,∴ .∵ ,
∴ .
∵ 与⊙O相切于点 ,∴ ,∴ .
∴ 是等腰直角三角形,
∴
","answer_json":["解:∵ 和 分别是弧 所对的圆心角和圆周角,∴ .∵ ,
∴ .
∵ 与⊙O相切于点 ,∴ ,∴ .
∴ 是等腰直角三角形,
∴
"],"explanation":"","pic_answer":"0","pic_explanation":"0","sub_explanation":null,"knowledge":null,"category":null,"done":false,"myanswer":"","sort2":1},{"question_id":"33289411","qsn_id":null,"question_type":"5","question_channel_type":"0","is_explain":"0","is_on_sale":"0","question_status":"0","question_tags":"","chid":"3","xd":"2","create_by":"1348058075_O54gFl","create_uid":"7693066","create_date":"2018-02-28 09:05:09","update_by":"","update_uid":"0","update_date":"2024-01-24 07:08:31","update_reason":"","audit_by":"","audit_uid":"0","audit_date":null,"audit2_by":"","audit2_uid":"0","audit2_date":null,"opinion":null,"parent_id":"6976057","sort":22,"is_objective":"0","difficult_index":"0","master_level":"0","exam_type":"0","evaluated":"0","region_ids":"","grade_id":"0","question_source":"","mode":"2","is_delete":"0","md5sum":"","title":"","kid_num":"0","paperid":"0","save_num":"0","oldqid":"0","explain_sort_need":"0","paper":null,"extra_file":"","question_text":"若CD=2,求BD的长.","options":"","answer":"解:由第(1)问可知 是等腰直角三角形,∴ ,∴ ,由勾股定理得 ,∴
","answer_json":["解:由第(1)问可知 是等腰直角三角形,∴ ,∴ ,由勾股定理得 ,∴
"],"explanation":"","pic_answer":"0","pic_explanation":"0","sub_explanation":null,"knowledge":null,"category":null,"done":false,"myanswer":"","sort2":2}],"knowledge":null,"category":null,"is_collect":false,"done":false,"myanswer":"","score":{"score":0,"subScore":[0,0]},"sort":21,"sort2":19,"is_use":0},{"question_id":"6976063","question_type":"7","question_channel_type":"28","is_explain":"1","is_on_sale":"1","question_status":"2","chid":"3","xd":"2","parent_id":"0","is_objective":"0","difficult_index":"3","master_level":"4","exam_type":"2","evaluated":"0","region_ids":"25","grade_id":"9","question_source":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷","mode":"2","title":"新农村社区改造中,有一部分楼盘要对外销售.某楼盘共23层,销售价格如下:第八层楼房售价为4000元/米<sup>2</sup>,从第八层起每上升一层...","kid_num":"2","paperid":"786101","save_num":"16","oldqid":"0","explain_sort_need":"0","paper":{"pid":"786101","title":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷"},"extra_file":"","question_text":"新农村社区改造中,有一部分楼盘要对外销售.某楼盘共23层,销售价格如下:第八层楼房售价为4000元/米2 , 从第八层起每上升一层,每平方米的售价提高50元;反之,楼层每下降一层,每平方米的售价降低30元.已知该楼盘每套楼房面积均为120米2 , 若购买者一次性付清所有房款,开发商有两种优惠方案:方案一:降价8%,另外每套楼房赠送a元装修基金;
方案二:降价10%,没有其他赠送.
当8<x≤23时,y=4000+50(x−8)=50x+3600.
∴所求函数关系式为 (x为正整数)
","answer_json":["解:当1≤x≤8时,y=4000−30(8−x)=30x+3760;当8<x≤23时,y=4000+50(x−8)=50x+3600.
∴所求函数关系式为 (x为正整数)
"],"explanation":"","pic_answer":"0","pic_explanation":"0","sub_explanation":null,"knowledge":null,"category":null,"done":false,"myanswer":"","sort2":1},{"question_id":"45067499","qsn_id":null,"question_type":"5","question_channel_type":"0","is_explain":"0","is_on_sale":"0","question_status":"0","question_tags":"","chid":"3","xd":"2","create_by":"1348058075_O54gFl","create_uid":"7693066","create_date":"2018-02-28 09:05:09","update_by":"","update_uid":"0","update_date":"2021-07-01 19:54:04","update_reason":"","audit_by":"","audit_uid":"0","audit_date":null,"audit2_by":"","audit2_uid":"0","audit2_date":null,"opinion":null,"parent_id":"6976063","sort":24,"is_objective":"0","difficult_index":"0","master_level":"0","exam_type":"0","evaluated":"0","region_ids":"","grade_id":"0","question_source":"","mode":"2","is_delete":"0","md5sum":"","title":"","kid_num":"0","paperid":"0","save_num":"0","oldqid":"0","explain_sort_need":"0","paper":null,"extra_file":"","question_text":"老王要购买第十六层的一套楼房,若他一次性付清购房款,请帮他计算哪种优惠方案更加合算.","options":"","answer":"解:当x=16时, 方案一楼房总费用: w1=120(50×16+3600)×92%-a=485760-a; 方案二楼房总费用:w2=120(50×16+3600)×90%=475200.
∴当w1<w2时,即485760-a<475200时,a>10560;
当w1=w2时,即485760-a=475200时,a=10560;
当w1>w2时,即485760-a>475200时,a<10560.
因此,当每套赠送装修基金多于10560元时,选择方案一合算; 当每套赠送装修基金等于10560元时,两种方案一样; 当每套赠送装修基金少于10560元时,选择方案二合算","answer_json":["解:当x=16时, 方案一楼房总费用: w1=120(50×16+3600)×92%-a=485760-a; 方案二楼房总费用:w2=120(50×16+3600)×90%=475200.
∴当w1<w2时,即485760-a<475200时,a>10560;
当w1=w2时,即485760-a=475200时,a=10560;
当w1>w2时,即485760-a>475200时,a<10560.
因此,当每套赠送装修基金多于10560元时,选择方案一合算; 当每套赠送装修基金等于10560元时,两种方案一样; 当每套赠送装修基金少于10560元时,选择方案二合算"],"explanation":"","pic_answer":"0","pic_explanation":"0","sub_explanation":null,"knowledge":null,"category":null,"done":false,"myanswer":"","sort2":2}],"knowledge":null,"category":null,"is_collect":false,"done":false,"myanswer":"","score":{"score":0,"subScore":[0,0]},"sort":23,"sort2":20,"is_use":0},{"question_id":"6976069","question_type":"7","question_channel_type":"28","is_explain":"1","is_on_sale":"1","question_status":"2","chid":"3","xd":"2","parent_id":"0","is_objective":"0","difficult_index":"3","master_level":"4","exam_type":"2","evaluated":"0","region_ids":"25","grade_id":"9","question_source":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷","mode":"2","title":"某商品的进价为每件40元,售价为每件50元,每个月可卖出210件;如果每件商品的售价每上涨1元,则每个月少卖10件(每件售价不能高于65元).设...","kid_num":"1","paperid":"786101","save_num":"47","oldqid":"0","explain_sort_need":"0","paper":{"pid":"786101","title":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷"},"extra_file":"","question_text":"某商品的进价为每件40元,售价为每件50元,每个月可卖出210件;如果每件商品的售价每上涨1元,则每个月少卖10件(每件售价不能高于65元).设每件商品的售价上x元(x为正整数),每个月的销售利润为y元.且 为整数
","answer_json":["解:由题意得: ,且 为整数
"],"explanation":"","pic_answer":"0","pic_explanation":"0","sub_explanation":null,"knowledge":null,"category":null,"done":false,"myanswer":"","sort2":1},{"question_id":"45067483","qsn_id":null,"question_type":"5","question_channel_type":"0","is_explain":"0","is_on_sale":"0","question_status":"0","question_tags":"","chid":"3","xd":"2","create_by":"","create_uid":"0","create_date":"2018-02-28 09:05:09","update_by":"","update_uid":"0","update_date":"2021-04-21 19:41:30","update_reason":"","audit_by":"","audit_uid":"0","audit_date":null,"audit2_by":"","audit2_uid":"0","audit2_date":null,"opinion":null,"parent_id":"6976069","sort":26,"is_objective":"0","difficult_index":"0","master_level":"0","exam_type":"0","evaluated":"0","region_ids":"","grade_id":"0","question_source":"","mode":"2","is_delete":"0","md5sum":"","title":"","kid_num":"0","paperid":"0","save_num":"0","oldqid":"0","explain_sort_need":"0","paper":null,"extra_file":"","question_text":"每件商品的售价定为多少元时,每个月可获得最大利润?最大的月利润是多少元?","options":"","answer":"解:由(1)中的 与 的解析式配方得: .∵ ,
∴当 时, 有最大值2402.5.
∵ 且 为整数,
当 时, , (元);当 时, , (元),
∴当售价定为每件55或56元时,每个月的利润最大,最大的月利润是2400元 。
","answer_json":["解:由(1)中的 与 的解析式配方得: .∵ ,
∴当 时, 有最大值2402.5.
∵ 且 为整数,
当 时, , (元);当 时, , (元),
∴当售价定为每件55或56元时,每个月的利润最大,最大的月利润是2400元 。
"],"explanation":"","pic_answer":"0","pic_explanation":"0","sub_explanation":null,"knowledge":null,"category":null,"done":false,"myanswer":"","sort2":2},{"question_id":"45067485","qsn_id":null,"question_type":"5","question_channel_type":"0","is_explain":"0","is_on_sale":"0","question_status":"0","question_tags":"","chid":"3","xd":"2","create_by":"","create_uid":"0","create_date":"2018-02-28 09:05:09","update_by":"","update_uid":"0","update_date":"2021-04-21 19:41:29","update_reason":"","audit_by":"","audit_uid":"0","audit_date":null,"audit2_by":"","audit2_uid":"0","audit2_date":null,"opinion":null,"parent_id":"6976069","sort":27,"is_objective":"0","difficult_index":"0","master_level":"0","exam_type":"0","evaluated":"0","region_ids":"","grade_id":"0","question_source":"","mode":"2","is_delete":"0","md5sum":"","title":"","kid_num":"0","paperid":"0","save_num":"0","oldqid":"0","explain_sort_need":"0","paper":null,"extra_file":"","question_text":"每件商品的售价定为多少元时,每个月的利润恰为2200元?","options":"","answer":"解:当 时, ,解得: , .∴当 时, ;当 时, .
∴当售价定为每件51或60元时,每个月的利润为2200元
∴当 时, ;当 时, .
∴当售价定为每件51或60元时,每个月的利润为2200元
∵AC=BC,AD=CD,OB=OC,∴∠A=∠B=∠1=∠2.
∵∠ACO=∠DCO+∠2,∴∠ACO=∠DCO+∠1=∠BCD .
又∵BD是直径,
∴∠BCD=90°,∴∠ACO=90°,
又点C在⊙O上,∴AC是⊙O的切线 。
","answer_json":["证明:如图,连接OC.∵AC=BC,AD=CD,OB=OC,∴∠A=∠B=∠1=∠2.
∵∠ACO=∠DCO+∠2,∴∠ACO=∠DCO+∠1=∠BCD .
又∵BD是直径,
∴∠BCD=90°,∴∠ACO=90°,
又点C在⊙O上,∴AC是⊙O的切线 。
"],"explanation":"","pic_answer":"0","pic_explanation":"0","sub_explanation":null,"knowledge":null,"category":null,"done":false,"myanswer":"","sort2":1},{"question_id":"45067503","qsn_id":null,"question_type":"5","question_channel_type":"0","is_explain":"0","is_on_sale":"0","question_status":"0","question_tags":"","chid":"3","xd":"2","create_by":"1348058075_O54gFl","create_uid":"7693066","create_date":"2018-02-28 09:05:09","update_by":"","update_uid":"0","update_date":"2024-01-24 07:08:38","update_reason":"","audit_by":"","audit_uid":"0","audit_date":null,"audit2_by":"","audit2_uid":"0","audit2_date":null,"opinion":null,"parent_id":"6976077","sort":29,"is_objective":"0","difficult_index":"0","master_level":"0","exam_type":"0","evaluated":"0","region_ids":"","grade_id":"0","question_source":"","mode":"2","is_delete":"0","md5sum":"","title":"","kid_num":"0","paperid":"0","save_num":"0","oldqid":"0","explain_sort_need":"0","paper":null,"extra_file":"","question_text":"若⊙0的半径为2,求 ABC的面积.∴∠CDO=∠DOC,即△DCO是等边三角形,
∴∠A=∠B=∠1=∠2=30°,CD=AD=2.
在Rt△BCD中,BC= .
又AC=BC,∴AC= .
如图,作CE⊥AB于点E.
在Rt△BEC中,∠B=30°,
∴CE= BC= ,
∴S△ABC= AB•CE= ×6× = 。
","answer_json":["解:由题意可得△DCO是等腰三角形.∵∠CDO=∠A+∠2,∠DOC=∠B+∠1,∴∠CDO=∠DOC,即△DCO是等边三角形,
∴∠A=∠B=∠1=∠2=30°,CD=AD=2.
在Rt△BCD中,BC= .
又AC=BC,∴AC= .
如图,作CE⊥AB于点E.
在Rt△BEC中,∠B=30°,
∴CE= BC= ,
∴S△ABC= AB•CE= ×6× = 。
"],"explanation":"","pic_answer":"0","pic_explanation":"0","sub_explanation":null,"knowledge":null,"category":null,"done":false,"myanswer":"","sort2":2}],"knowledge":null,"category":null,"is_collect":false,"done":false,"myanswer":"","score":{"score":0,"subScore":[0,0]},"sort":28,"sort2":22,"is_use":0},{"question_id":"6976083","question_type":"7","question_channel_type":"28","is_explain":"1","is_on_sale":"1","question_status":"2","chid":"3","xd":"2","parent_id":"0","is_objective":"0","difficult_index":"5","master_level":"4","exam_type":"2","evaluated":"0","region_ids":"25","grade_id":"9","question_source":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷","mode":"2","title":"如图甲,抛物线y=x2-+bx+c交x轴于点A(-3,0)和点B,交y轴于点C(0,3).","kid_num":"4","paperid":"786101","save_num":"57","oldqid":"0","explain_sort_need":"0","paper":{"pid":"786101","title":"云南省昭通市彝良县2017-2018学年九年级上学期数学期末考试试卷"},"extra_file":"","question_text":"如图甲,抛物线y=x2-+bx+c交x轴于点A(-3,0)和点B,交y轴于点C(0,3).","options":"","sub_explanation":null,"list":[{"question_id":"45067487","qsn_id":null,"question_type":"5","question_channel_type":"0","is_explain":"0","is_on_sale":"0","question_status":"0","question_tags":"","chid":"3","xd":"2","create_by":"1348058075_O54gFl","create_uid":"7693066","create_date":"2018-02-28 09:05:09","update_by":"","update_uid":"0","update_date":"2024-01-24 07:08:30","update_reason":"","audit_by":"","audit_uid":"0","audit_date":null,"audit2_by":"","audit2_uid":"0","audit2_date":null,"opinion":null,"parent_id":"6976083","sort":30,"is_objective":"0","difficult_index":"0","master_level":"0","exam_type":"0","evaluated":"0","region_ids":"","grade_id":"0","question_source":"","mode":"2","is_delete":"0","md5sum":"","title":"","kid_num":"0","paperid":"0","save_num":"0","oldqid":"0","explain_sort_need":"0","paper":null,"extra_file":"","question_text":"求抛物线的函数表达式;","options":"","answer":"解:把A(−3,0),C(0,3)代入y=−x2+bx+c,得 解得故该抛物线的解析式为:y=−x2−2x+3 .
","answer_json":["解:把A(−3,0),C(0,3)代入y=−x2+bx+c,得 解得故该抛物线的解析式为:y=−x2−2x+3 .
"],"explanation":"","pic_answer":"0","pic_explanation":"0","sub_explanation":null,"knowledge":null,"category":null,"done":false,"myanswer":"","sort2":1},{"question_id":"45067489","qsn_id":null,"question_type":"5","question_channel_type":"0","is_explain":"0","is_on_sale":"0","question_status":"0","question_tags":"","chid":"3","xd":"2","create_by":"1348058075_O54gFl","create_uid":"7693066","create_date":"2018-02-28 09:05:09","update_by":"","update_uid":"0","update_date":"2024-01-24 07:08:30","update_reason":"","audit_by":"","audit_uid":"0","audit_date":null,"audit2_by":"","audit2_uid":"0","audit2_date":null,"opinion":null,"parent_id":"6976083","sort":31,"is_objective":"0","difficult_index":"0","master_level":"0","exam_type":"0","evaluated":"0","region_ids":"","grade_id":"0","question_source":"","mode":"2","is_delete":"0","md5sum":"","title":"","kid_num":"0","paperid":"0","save_num":"0","oldqid":"0","explain_sort_need":"0","paper":null,"extra_file":"","question_text":"若点P在抛物线上,且 ,求点P的坐标;","options":"","answer":"解:设 ;P(x,−x2−2x+3) ,由(1)知,该抛物线的解析式为y=−x2−2x+3,则B(1,0).∵S△AOP=4S△BOC ,∴ ×3×|−x2−2x+3|=4× ×1×3.
整理,得(x+1)2=0或x2+2x−7=0,
解得x=−1或x=−1± .
则符合条件的点P的坐标为:(−1,4)或(−1+ ,−4)或(−1− ,−4) 。
","answer_json":["解:设 ;P(x,−x2−2x+3) ,由(1)知,该抛物线的解析式为y=−x2−2x+3,则B(1,0).∵S△AOP=4S△BOC,∴ ×3×|−x2−2x+3|=4× ×1×3.
整理,得(x+1)2=0或x2+2x−7=0,
解得x=−1或x=−1± .
则符合条件的点P的坐标为:(−1,4)或(−1+ ,−4)或(−1− ,−4) 。
"],"explanation":"","pic_answer":"0","pic_explanation":"0","sub_explanation":null,"knowledge":null,"category":null,"done":false,"myanswer":"","sort2":2},{"question_id":"45067491","qsn_id":null,"question_type":"5","question_channel_type":"0","is_explain":"0","is_on_sale":"0","question_status":"0","question_tags":"","chid":"3","xd":"2","create_by":"1348058075_O54gFl","create_uid":"7693066","create_date":"2018-02-28 09:05:09","update_by":"","update_uid":"0","update_date":"2024-01-24 07:08:30","update_reason":"","audit_by":"","audit_uid":"0","audit_date":null,"audit2_by":"","audit2_uid":"0","audit2_date":null,"opinion":null,"parent_id":"6976083","sort":32,"is_objective":"0","difficult_index":"0","master_level":"0","exam_type":"0","evaluated":"0","region_ids":"","grade_id":"0","question_source":"","mode":"2","is_delete":"0","md5sum":"","title":"","kid_num":"0","paperid":"0","save_num":"0","oldqid":"0","explain_sort_need":"0","paper":null,"extra_file":"","question_text":"如图乙,设点Q是线段AC上的一动点,作DQ x轴,交抛物线于点D,求线段DQ长度的最大值.","options":"","answer":"解:设直线AC的解析式为y=kx+t,将A(−3,0),C(0,3)代入,得 解得即直线AC的解析式为y=x+3.
设Q点坐标为(x,x+3)(−3≤x≤0),则D点坐标为(x,−x2−2x+3),
QD=(−x2−2x+3)−(x+3)=−x2−3x=− + ,
∴当x=− 时,QD有最大值 。
","answer_json":["解:设直线AC的解析式为y=kx+t,将A(−3,0),C(0,3)代入,得 解得即直线AC的解析式为y=x+3.
设Q点坐标为(x,x+3)(−3≤x≤0),则D点坐标为(x,−x2−2x+3),
QD=(−x2−2x+3)−(x+3)=−x2−3x=− + ,
∴当x=− 时,QD有最大值 。
"],"explanation":"","pic_answer":"0","pic_explanation":"0","sub_explanation":null,"knowledge":null,"category":null,"done":false,"myanswer":"","sort2":3}],"knowledge":null,"category":null,"is_collect":false,"done":false,"myanswer":"","score":{"score":0,"subScore":[0,0,0]},"sort":30,"sort2":23,"is_use":0}],"scores":[],"sum_score":0,"question_num":9}],32,[{"is_old_zujuan786101":{"1":""}},{"is_old_zujuan786101":""},{"is_old_zujuan786101":{"list":["","",""]}}],[{"question_id":"6976013","parent_id":"0","question_type":"4","myanswer":{"1":""},"X1":0,"x2":0},{"question_id":"6976015","parent_id":"0","question_type":"4","myanswer":{"1":""},"X1":1,"x2":0},{"question_id":"6976017","parent_id":"0","question_type":"4","myanswer":{"1":""},"X1":2,"x2":0},{"question_id":"6976019","parent_id":"0","question_type":"4","myanswer":{"1":""},"X1":3,"x2":0},{"question_id":"6976021","parent_id":"0","question_type":"4","myanswer":{"1":""},"X1":4,"x2":0},{"question_id":"6976023","parent_id":"0","question_type":"4","myanswer":{"1":""},"X1":5,"x2":0},{"question_id":"3581315","parent_id":"0","question_type":"1","myanswer":"","X1":6,"x2":0},{"question_id":"6976027","parent_id":"0","question_type":"1","myanswer":"","X1":7,"x2":0},{"question_id":"6976029","parent_id":"0","question_type":"1","myanswer":"","X1":8,"x2":0},{"question_id":"6976031","parent_id":"0","question_type":"1","myanswer":"","X1":9,"x2":0},{"question_id":"6976033","parent_id":"0","question_type":"1","myanswer":"","X1":10,"x2":0},{"question_id":"2594385","parent_id":"0","question_type":"1","myanswer":"","X1":11,"x2":0},{"question_id":"6976037","parent_id":"0","question_type":"1","myanswer":"","X1":12,"x2":0},{"question_id":"6976039","parent_id":"0","question_type":"1","myanswer":"","X1":13,"x2":0},{"question_id":"6976041","parent_id":"0","question_type":"7","myanswer":"","X1":14,"x2":0},{"question_id":"45067495","parent_id":"6976041","question_type":"5","myanswer":"","X1":15,"x2":0},{"question_id":"45067497","parent_id":"6976041","question_type":"5","myanswer":"","X1":15,"x2":1},{"question_id":"6976047","parent_id":"0","question_type":"5","myanswer":"","X1":15,"x2":0},{"question_id":"6976049","parent_id":"0","question_type":"5","myanswer":"","X1":16,"x2":0},{"question_id":"6976051","parent_id":"0","question_type":"7","myanswer":"","X1":17,"x2":0},{"question_id":"45067477","parent_id":"6976051","question_type":"5","myanswer":"","X1":18,"x2":0},{"question_id":"45067479","parent_id":"6976051","question_type":"5","myanswer":"","X1":18,"x2":1},{"question_id":"6976057","parent_id":"0","question_type":"7","myanswer":"","X1":18,"x2":0},{"question_id":"33289351","parent_id":"6976057","question_type":"5","myanswer":"","X1":19,"x2":0},{"question_id":"33289411","parent_id":"6976057","question_type":"5","myanswer":"","X1":19,"x2":1},{"question_id":"6976063","parent_id":"0","question_type":"7","myanswer":"","X1":19,"x2":0},{"question_id":"45067493","parent_id":"6976063","question_type":"5","myanswer":"","X1":20,"x2":0},{"question_id":"45067499","parent_id":"6976063","question_type":"5","myanswer":"","X1":20,"x2":1},{"question_id":"6976069","parent_id":"0","question_type":"7","myanswer":"","X1":20,"x2":0},{"question_id":"45067481","parent_id":"6976069","question_type":"5","myanswer":"","X1":21,"x2":0},{"question_id":"45067483","parent_id":"6976069","question_type":"5","myanswer":"","X1":21,"x2":1},{"question_id":"45067485","parent_id":"6976069","question_type":"5","myanswer":"","X1":21,"x2":2},{"question_id":"6976077","parent_id":"0","question_type":"7","myanswer":"","X1":21,"x2":0},{"question_id":"45067501","parent_id":"6976077","question_type":"5","myanswer":"","X1":22,"x2":0},{"question_id":"45067503","parent_id":"6976077","question_type":"5","myanswer":"","X1":22,"x2":1},{"question_id":"6976083","parent_id":"0","question_type":"7","myanswer":"","X1":22,"x2":0},{"question_id":"45067487","parent_id":"6976083","question_type":"5","myanswer":"","X1":23,"x2":0},{"question_id":"45067489","parent_id":"6976083","question_type":"5","myanswer":"","X1":23,"x2":1},{"question_id":"45067491","parent_id":"6976083","question_type":"5","myanswer":"","X1":23,"x2":2}]],"_timestamp":null,"action":"test"}