已知2x+y+4,xy=2,求-4x²y²-y³x-4x³y的值
问题描述:
已知2x+y+4,xy=2,求-4x²y²-y³x-4x³y的值
答
= -xy(y²+4xy+4x²)
= -xy(2x+y)²
= -2×4²
= -32