如何将x^3-11x^2+31x-21因式分解
问题描述:
如何将x^3-11x^2+31x-21因式分解
答
先把他拆开为X^3-11X^2+10X+21X-21然后前三项提一个X,得X(X-11X+10)+21(X-1)然后前边在变形X(X-10)(X-1)+21(X-1)提一个(X-1)得(X-1)(X^2-10X+21)最后的(X-1)(X-3)(X-7)然后OK!