已知:a+b=3,x-y=1,求a2+2ab+b2-x+y的值.
问题描述:
已知:a+b=3,x-y=1,求a2+2ab+b2-x+y的值.
答
∵a+b=3,x-y=1,
∴a2+2ab+b2-x+y
=(a+b)2-(x-y)
=9-1=8.