已知x²-3xy=5,xy+y²=3,求x²-2xy+y²的值
问题描述:
已知x²-3xy=5,xy+y²=3,求x²-2xy+y²的值
答
x²-3xy=5,xy+y²=3,
x²-2xy+y²=x²-3xy+xy+y²=5+3 = 8