记函数f(x)=√[2-(x+3)/(x+1)]的定义域是A,g(x)=lg[(x-a-1)(2a-x)](a

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记函数f(x)=√[2-(x+3)/(x+1)]的定义域是A,g(x)=lg[(x-a-1)(2a-x)](a
记函数f(x)=√[2-(x+3)/(x+1)]的定义域是A,g(x)=lg[(x-a-1)(2a-x)](a<1)的定义域为B.
(1)求A (2)若B含于A,求实数a的取值范围
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记函数f(x)=√[2-(x+3)/(x+1)]的定义域是A,g(x)=lg[(x-a-1)(2a-x)](a
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2aB含于A
则2a所以a<=-2,a>=1/2
所以a<=-2,1/2<=a<1