借助立方差公式a³-b³=(a-b)(a²+ab+b²)分解因式,解方程：x³-2x²+4x-8=0(x³-8)-2x(x-2)=0(x-2)(x²+2x+4)-2x(x-2)=0(x-2)(x²+4)=0∴x=2