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高三文科入学考试答案1-6BDCBAC7-12ACBDAB13.214.115.1−16.[0,)+17.计算:(1)72;(2)111.【详解】(1)2log351log25lgln2100e+++21log32225log5lg10ln2e−=+++()12232=+−++1732
2=+=.(2)()060.2534682237−++()113234412223=++12108111=++=.18(1)(),2222,−−+;(2)(),221,22−−.【详解】(1)若p为真命
题,则方程220xax++=有实数根,即280a=−,解得:22a−或22a,即a的取值范围为(),2222,−−+.(2)若q为真命题,则()0,1x,2ax成立,即1a.若pq为真,pq为假,则p,q一真一假.若p真q假,则
22221aaa−或,所以22a−;若p假q真,则22221aa−,所以122a.综上,a的取值范围为(),221,22−−.19.(1)1a=;(2)(0,2试题解析:(1)∵函数()2log(0)1xafxax+=−为奇函数,∴()(
)0fxfx+−=,即22loglog011xaxaxx+−++=−−−,即222log01xax−=−,2211xax−=−,1a=.(2)由(1)知()21log1xfxx+=−,因为(1,4x,()2log1mfxx−恒成立,所以111xmxx
+−−,因为(1,4x,所以01mx+在(1,4x上成立,所以02m.即实数m的取值范围是(0,2.20.(1)单调减区间为()0,2,单调增区间为()2,+;(2)()242minfxln=−,1()2maxfx=
.()1定义域为()0,+,由题得()4'fxxx=−,令()0fx=,2x=.x02x2x()fx-+所以()fx的单调减区间为()0,2,单调增区间为()2,+;(2)由()1得,()fx在)1,2单调递减,在2,e单调递增,所以()()2242minfx
fln==−,又()112f=,()2142fee=−,因为()211422fee=−,所以()()2242minfxfln==−,1()2maxfx=.21.(1)当a≤0时,f(x)的单调增区间为(-∞,+∞);当a>0时,f(x)的单调增区间为(lna,+
∞).(2)(-∞,0].【详解】(1)若,则,此时的单调增区间为若,令,得此时的单调增区间为(2)在R上单调递增,则在R上恒成立即恒成立即,因为当时,所以-0+22.(1)()xfxex=+;(2)(,e1]m−−.【详解】(1)()exfxa=+,()012fa=+=,解得1a
=,()011fb=+=,解得0b=,所以()xfxex=+.(2)当0x时,21xexxmx+++,即e11xmxxx−−+.令()e11(0)xhxxxxx=−−+,则()()22e11xxxhxx−−+=()()21e1xxxx−−−
=.令()e1(0)xxxx=−−,()e10xx=−,当()0,x+时,()x单调递增,()()00x=,则当()0,1x时,即()0hx,所以()hx单调递减;当()1,x+时,即()0hx,所以()hx单调递增,综上,()()min11hxhe==−
,所以(,e1m−−.