解方程：x^4+2x^3-18x^2-10x+25=0
问题描述：
解方程：x^4+2x^3-18x^2-10x+25=0
答
x^4+2x^3-18x^2-10x+25=0
x^4-x^3+3x^3-3x^2-15x^2+15x-25x+25=0
(x-1)(x^3+3x^2-15x-25)=0
(x-1)(x^3+5x^2-2x^2-10x-5x-25)=0
(x-1)(x+5)(x^2-2x-5)=0
x-1=0或x+5=0或x^2-2x-5
解得
x=1或-5或1±√6