1郑州市2026年高中毕业年级第一次质量预测数学评分参考一、选择题:本题共8小题,每小题5分,共40分.题号12345678答案BAADCDBC二、多选题:本题共3小题,每小题6分,共18分.题号91011答案ABDACACD三、填空题:本题共3小题,每小题5分,共15分.12.413.6014.35四、解答题:本题共5小题,共77分.解答应写出文字说明、证明过程或演算步骤.15.解:(1)1010111155,91.7,1010iiiixxyy...........................................................2分1211022101055950105591.71103ˆ0.67,385001055165010iiiiiyxxxybx...............................................5分ˆˆ91.70.675554.85aybx,.........................................................................6分所以,加工时间y关于零件个数x的经验回归方程是ˆ0.6,754.85yx,.....................7分(2)(ⅰ)120x当时,ˆ0.6712054.85135.25.y..................................................9分所以120个零件任务的回归预测时间135.25<144,因此低于现行标准时间........10分(ⅰⅰ)由于回归预测显示实际所需时间(约135.25分)比标准时间(144分)少9分钟,说明按照现行标准,工人很容易拿到奖励(实际效率更高).如果车间希望控制奖励发放比例或更符合实际效率,应考虑调低标准时间,如调整到接近预测的.13.112025.135个分/使标准更贴近真实加工能力.....................................................................................13分16.解:(1)在ABC中,由1tantantantanCBCB得1tantan1tantanCBCB,21tan)(CB..................................................................2分又)tan(tanCBA,1tanA,........................................................................3分A0又,4A...........................................................................................4分6a,3c,由正弦定理得.236223sinsinaAcC.........................6分ac,323C或........................................................................................7分(2)因为ABC为锐角三角形,所以3C,...........................................................8分426)sin(sinCAB,............................................................................10分0NCNBNA,的重心,是ABCN..........................................................11分,4334263661sin6131BacSSABCNBC......................................................12分所以NBC的面积为433..................................................................................15分17.解:(1)在矩形CDEF中,1,2,CDDE点BA,分别是的中点,,CFDE所以四边形ABCD和EFBA是全等的正方形,所以,BDACAEAB........................2分又因为平面ABCD平面EFBA,平面ABCD平面,EFBAABAE平面EFBA,所以AE平面ABCD...............................................................................................4分因为BD平面ABCD,所以AEBD......................................................................5分又因为,BDACAEACA,AEAC,平面AEC,所以BD平面AEC.................................................................................................6分3(2)以B为原点,BCBFBA,,所在直线分别为轴轴、轴、zyx,建立如图所示的空间直角坐标系.则0,0,0,1,0,0,1,1,0BAE,0,1,0,0,0,1,1,0,1FCD,..............................7分则)(101,,CA,)(100,,CB,aBQCP,则)22,0,22(22aaCAaCP,)0,22,22(22aaBEaBQ,)122,220(aaBQCBPCPQ,,.........................................
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