因式分解:9a2(x-y)+4b2(y-x)
问题描述:
因式分解:9a2(x-y)+4b2(y-x)
答
9a2(x-y)+4b2(y-x)
=9a2(x-y)-4b2(x-y)
=(x-y)(9a2-4b2)
=(x-y)(3a+2b)(3a-2b).