先化简再求值[3x/(x+2)-x/(x-2)]÷2x/(x^2-4)
问题描述:
先化简再求值[3x/(x+2)-x/(x-2)]÷2x/(x^2-4)
x=2010
答
[3x/(x+2)-x/(x-2)]÷2x/(x^2-4)
分子分母同时乘以x²-4
=[3x(x-2)-x(x+2)]/2x
=(3x²-6x-x²-2x)/2x
=(2x²-8x)/2x
=x-4
=2010-4
=2006