用公式法进行因式分解 x(x+4)+4 25(x+y)²-9(x+y)² (x-y)(x²-xy+y²)+xy(y-x) 2a&su
问题描述:
用公式法进行因式分解 x(x+4)+4 25(x+y)²-9(x+y)² (x-y)(x²-xy+y²)+xy(y-x) 2a&su
答
题目不是很清楚
x(x+4)+4=(x+2)^2
(x+y)²-9=(x+y-3)(x+y+3)
(x-y)(x²-xy+y²)+xy(y-x) =(x-y)(x²-xy+y²-1)