衡水金卷先享题 2025-2026学年度高三一轮复习摸底测试卷·摸底卷 数学A(一)1答案
数学参考答案及解析题号1235681011答案BAADCCADABDBCD1.B【解析】易知集合U={-1,0,1,2},A={0,1},故CuA={-1,2}.故选B.2.A【解析】设复数x=a+bi(a,b∈R),则=a-bi,2x+=2(a+bi)+a-bi=3-6i,3a=3,b=-6,a=1,b=-6,x=1-6i,故其虚部为-6,故选A3.A【解析】若a1,a2,a3,a4,a5成等差数列,则2a3=a+a5成立;若取a1,a2,a3,a4,a5依次为1,2,5,6,9,此时满足2a3=a1+as,但a1,a2,a3,a4,as不成等差数列,故2a3=a1+as不能推出a1,a2,a3,a4,as成等差数列,故“a1,a2,a3,a4,as成等差数列”是“2a3=a1十as”的充分不必要条件,故选A.4.C【解析】由题意得8y(8十8)=8,当且仅当8y时,等号成立,故选C.25.C【解析】f(x)=2十x单调递增,f(一1)=<0,f(0)=1>0,-10,
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