ѵ8 ż뵥()
ĵԡżǸ߿صȵ֮һرʵӦøͻ.Ҫѧʽ⣬ջγӦʶ.
ѵų
()֪żf(x)(0+)Ϊf(2)=0,ⲻʽf[log2(x2+5x+4)]0.
̽
[1]֪溯f(x)Ƕ(-33)ϵļ㲻ʽf(x-3)+f(x2-3)<0,費ʽ⼯ΪAB=A{x|1x },g(x)=-3x2+3x-4(xB)ֵ.
ͼںʵۺĿۺ֪ʶͽＶĿ.
֪ʶУҪݺȥ.
Ŀʽеġfȥѵ㣬κڸϵֵʱѧ©.
뷽żȥfţתΪxcosʽνϽмֵ.
⣺ x0,0
֡f(x)溯f(x-3)<-f(x2-3)=f(3-x2),f(x)(-33)Ǽ
x-3>3-x2,x2+x-6>0,x>2x<-3,ϵ2
B=A{x|1x }={x|1x< },g(x)=-3x2+3x-4=-3(x- )2- ֪g(x)BΪg(x)max=g(1)=-4.
[2]֪溯f(x)ĶΪRf(x)[0+)Ƿʵm,ʹf(cos2-3)+f(4m-2mcos)>f(0)Цȡ[0, ]?ڣʵmķΧڣ˵.
ͼ̽⣬Ҫ鿼ۺϷ˼άԼĿ.
֪ʶУҪݺĵԺżԣõȼת˼뷽תΪκڸϵֵ.
úۺȥ⣬رõȼת˼뷽.
뷽Ҫõȼת˼ͷ۵˼.
⣺f(x)Rϵ溯[0+)f(x)Rϵ.Dzʽɵȼ۵תΪf(cos2-3)>f(2mcos-4m),
cos2-3>2mcos-4m,cos2-mcos+2m-2>0.
t=cos,ȼ۵תΪg(t)=t2-mt+2m-2=(t- )2- +2m-2[01]ϵֵΪתΪg(t)[01]ϵСֵΪ.
൱ <0,m<0ʱg(0)=2m-2>0 m>1m<0;
0 1ʱ0m2ʱg(m)=- +2m-2>0
4-2
>1,m>2ʱg(1)=m-1>0 m>1.m>2
ϣĿҪmֵڣȡֵΧm>4-2 .
ѵ漰ԼķҪУ
(1)żԺ͵ȥйغۺĿ.ĿҪмԦ֪ʶۺϷͽ.
(2)Ӧ.úżԺ͵ԽʵĹУҪõȼתνϵ˼뷽нϸӡʽתΪļʽȥ.رǣúĵʵӦеֵ.
2017ɿ⣺2017˸߿ʷƾѧģ
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