2x(x^2+9)=20x^2

问题描述:

2x(x^2+9)=20x^2

2x(x^2+9)=20x^2
2x^3+18x-20X^2=0
x^3-10x^2+9x=0
x(x^2-10x+9)=0
x(x-1)(x-9)=0
x1=0 x2=1 x3=9