2x/(x²-4)-1/(x-2)

问题描述:

2x/(x²-4)-1/(x-2)

2x/(x²-4)-1/(x-2)
=2x/(x^2-4)-(x+2)/(x^2-4)
=(2x-x-2)/(x^2-4)
=(x-2)/[(x+2)(x-2)]
=1/(x+2)

原式=2x/(x+2)(x-2)-(x+2)/(x+2)(x-2)
=[2x-(x+2)]/(x+2)(x-2)
=(x-2)/(x+2)(x-2)
=1/(x+2)