因式分解;x的3次方减x的平方减10x减8
问题描述：
因式分解;x的3次方减x的平方减10x减8
答
x³-x²-10x-8
=x³-4x²+3x²-10x-8
=x²(x-4)+(x-4)(3x+2)
=(x-4)(x²+3x+2)
=(x-4)(x+1)(x+2)
就是分开再提取公因式。
答
x³－x²－10x－8
=(x³－x²－12x)＋(2x－8)
=x(x²－x－12)＋2(x－4)
=x(x－4)(x＋3)＋2(x－4)
=(x－4)[x(x＋3)＋2]
=(x－4)(x²＋3x＋2)
=(x－4)(x＋1)(x＋2)
答
x³-x²-10x-8
=x³-4x²+3x²-10x-8
=x²(x-4)+(x-4)(3x+2)
=(x-4)(x²+3x+2)
=(x-4)(x+1)(x+2)