Question

(高中数学)请问像x^3-3x+2=0,这样的方程应该怎样解?

Answer 1

x^3-3x+2=0

(x^3-x)-(2x-2)=0

x(x^2-1)-2(x-1)=0

x(x-1)(x+1)-2(x-1)=0

(x-1)(x^2+x-2)=0

(x-1)(x-1)(x+2)=0

(x-1)^2(x+2)=0

x-1=0或x+2=0

x=1或x=-2