若U=R,A={x|(1/2)^(x 2)(x 3)>1},B={x|log3(x-a)
问题描述:
若U=R,A={x|(1/2)^(x 2)(x 3)>1},B={x|log3(x-a)
答
(1/2)^(x +2)(x- 3)>1=(1/2)^0
y=(1/2)^x递减,
所以有:
(x+2)(x-3)