1/x+3+1-x/6+2x-6/x^2-9. 分式加减

问题描述:

1/x+3+1-x/6+2x-6/x^2-9. 分式加减

原式=1/(x+3)-(x-1)/2(x+3)-6/(x+3)(x-3)
=(2x-6-x²+4x-3-12)/2(x+3)(x-3)
=(-x²+6x-21)/2(x+3)(x-3)
=(-x²+6x-21)/(2x²-18)