第1页共11页三明市2024年普通高中高三毕业班质量检测数学参考答案及评分细则评分说明:1.本解答给出了一种或几种解法供参考,如果考生的解法与本解答不同,可根据试题的主要考查内容比照评分标准制定相应的评分细则.2.对计算题,当考生的解答在某一步出现错误时,如果后继部分的解答未改变该题的内容和难度,可视影响的程度决定后继部分的给分,但不得超过该部分正确解答应给分数的一半;如果后继部分的解答有较严重的错误,就不再给分.3.解答右端所注分数,表示考生正确做到这一步应得的累加分数.4.只给整数分数.选择题和填空题不给中间分.一、选择题:本大题考查基础知识和基本运算.每小题5分,满分40分.1.C2.C3.D4.A5.A6.B7.B8.C二、选择题:本大题考查基础知识和基本运算.每小题6分,满分18分.全部选对的得6分,部分选对的得部分分,有选错的得0分.9.BC10.ACD11.BCD三、填空题:本大题考查基础知识和基本运算.每小题5分,满分15分.12.613.1,3e14.6,7,8,9,21(第一空2分,第二空3分)四、解答题:本大题共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.解法一:(1)证明:取BD的中点M,连接PMMC、,·······················1分 BPD△和BCD△均为等边三角形,∴BDPM,BDCM.··································································2分又PMCMM,∴BD平面CPM,·········································································3分CP又平面CPM,∴BDCP.····················································································4分(2)以M为原点,,MBMC所在直线为,xy轴,过M作平面BCD的垂线所在直线为z轴,如图所示建立空间直角坐标系,···········································5分 平面ABD平面PBD,平面ABD平面PBDBD,PM平面PBD,PMBD∴PM平面ABD. PBD△和CBD△均为等边三角形,∴3PMMCPC,60PMC,{#{QQABDYaEoggoAJJAABhCQQUgCkAQkAEAAKoGwAAIMAAAiBFABCA=}#}第2页共11页∴330,,22P,0,3,0C,1,0,0B,··············································6分∴331,,22BP,1,3,0BC.330,,22MP设平面PBC的法向量为(,,)xyzm∴0,0BPBCmm即330,2230xyzxy取1z,则3,3,1m,···································································8分平面ABD的法向量330,,22MP,·················································10分设平面ABD与平面PBC的夹角为,∴coscos,MPMPMPnnn33913313··································12分∴平面ABD与平面PBC夹角的余弦值为3913.····································13分解法二:(1)同解法一······································································4分(2)如图,取MC的中点E为原点,连接PE,过点E作//EFMB,交BC于点F,由(1)知CMBD,EFMC,又由(1)知BD平面CPM,PE又平面CPM,∴BDPE, PBD△和CBD△均为等边三角形且棱长为2,∴3PMMCPC,PEMC,BDMCM...
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