Question

已知单项式-3a^2-mb与ab^n+1是同类项,求代数式m^2-(-3mn+3n^2)+2n^2的值.

Answer 1

∵-3a^2-mb与ab^n+1是同类项

∴2-m=1

n+1=0

即：m=1,n=-1

∴m²-(-3mn+3n²)+2n²

=m²+3mn-n²

=1-3-1

=-3