已知a=m/2+1.b=m/2+2,c=m/2+3,求:a^2+2ab+b^2-2ac+c^2-2bc的值(要过程和结果)

问题描述:

已知a=m/2+1.b=m/2+2,c=m/2+3,求:a^2+2ab+b^2-2ac+c^2-2bc的值
(要过程和结果)

a^2+2ab+b^2-2ac+c^2-2bc
=(-a-b+c)^2
=(-m/2-1-m/2-2+m/2+3)^2
=(-m/2)^2
=m^2/4