已知(m-1)^2+|m+n|=0,求4m^2+6n^2-mn-2m^2+5n^2-3mn的值

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已知(m-1)^2+|m+n|=0,求4m^2+6n^2-mn-2m^2+5n^2-3mn的值

已知(m-1)^2+|m+n|=0,求4m^2+6n^2-mn-2m^2+5n^2-3mn的值
已知(m-1)^2+|m+n|=0,求4m^2+6n^2-mn-2m^2+5n^2-3mn的值

已知(m-1)^2+|m+n|=0,求4m^2+6n^2-mn-2m^2+5n^2-3mn的值

(m-1)²+|m+n|=0
m-1=0 m+n=0
m=1 n=-1
于是
4m²+6n²-mn-2m²+5n²-3mn
=4m²-2m²+5n²+6n²-mn-3mn
=2m²+11n²-4mn
=2×1²+11×(-1)²-4×1×(-1)
=2+11+4
=17