記函數(shù)f(x)=√[2-(x+3)/(x+1)]的定義域是A,g(x)=lg[(x-a-1)(2a-x)](a
記函數(shù)f(x)=√[2-(x+3)/(x+1)]的定義域是A,g(x)=lg[(x-a-1)(2a-x)](a<1)的定義域為B.
(1)求A (2)若B含于A,求實數(shù)a的取值范圍
請告訴我答案及解題過程!謝謝!
數(shù)學人氣:881 ℃時間:2019-12-11 21:03:03
優(yōu)質(zhì)解答
2-(x+3)/(x+1)>=0
(2x+2-x-3)/(x+1)>=0
(x-1)(x+1)>=0
x+1在分母,不等于0
所以A={x|x>=1,x<-1}
(x-a-1)(2a-x)>0
[x-(a+1)](x-2a)<0
a<1,所以a+1>2a
所以2a
B含于A
則2a
所以a<=-2,a>=1/2
所以a<=-2,1/2<=a<1
我來回答
類似推薦