设全集I={2,3,x²+2x-3},集合A={|2x-1|,2},C1A={5},求实数x的值?
问题描述:
设全集I={2,3,x²+2x-3},集合A={|2x-1|,2},C1A={5},求实数x的值?
答
∵x^2+2x-3=5 & |2x-1|=3
∴ x^2+2x-8=0 & 4x^2-4x-8=0
=> [ x1=2 ,x2=-4] & [x1=2 ,x2=-1]
∴x=2