5x(x-y)的平方+4y(y-x)怎么解?
问题描述:
5x(x-y)的平方+4y(y-x)怎么解?
答
原式=5x(x-y)²-4y(x-y)
=(x-y)[5x(x-y)-4y]
=(x-y)(5x²-5xy-4y)