求(2x+y)(4x平方-2xy+y平方+y平方)化简
问题描述:
求(2x+y)(4x平方-2xy+y平方+y平方)化简
答
两个y²?
应该是(2x+y)(4x²-2xy+y²)
=2x(4x²-2xy+y²)+y(4x²-2xy+y²)
=8x³-4x²y+2xy²+4x²y-2xy²+y³
=8x³+y³