还是一道数学题目

（m-1)^2+|6m+3n|=0
m-1=0,6m+3n=0
m=1,n=-2
(4m^2-mn-6n^2)-2(m^2-3mn-5n^2)
=4m^2-mn-6n^2-2m^2+6mn+10n^2
=2m^2+5mn+4n^2
=2-10+16
=8

m=1 n=-2 你再算一下,大概是8

(m-1)^2+绝对值6m+3n=0 推出m-1=0,m=1 和6m+3n=0,m=1已证，n=-2
所以原式=(4*1*1+2-6*4)-2*(1*1+3*2*1-5*4)
=8