已知:(a-5)^2+lb+3l=?则(a-3)^2+(b+2)^2=?

问题描述:

已知:(a-5)^2+lb+3l=?则(a-3)^2+(b+2)^2=?

(a-5)^2+lb+3l=?
号是多少啊?
看着不明不白
要是(a-5)^2+lb+3l=0
那就 (a-5)^2>=0 lb+3l>=0
而(a-5)^2+lb+3l=0
==>(a-5)^2=0 lb+3l=0
==>a=5 b=-3
==>(a-3)^2+(b+2)^2=5