解方程:(x^3+2)/(x^2-x+1)+(x^3-9)/(x^2+2x+4)=2x-1
问题描述:
解方程:(x^3+2)/(x^2-x+1)+(x^3-9)/(x^2+2x+4)=2x-1
答
化简如下:
(x^3+2)(x+1)/(x^3+1)+(x^3-9)(x-2)/(x^3-8)=2x-1
(x^3+1+1)(x+1)/(x^3+1)+(x^3-8-1)(x-2)/(x^3-8)=2x-1
(x+1)+(x+1)/(x^3+1)+(x-2)-(x-2)/(x^3-8)=2x-1
(x+1)/(x^3+1)-(x-2)/(x^3-8)=0
1/(x^2-x+1)=1/(x^2+2x+4)
x^2-x+1=x^2+2x+4
3x=-3
x=-1