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.
问题描述:
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.
求...
答
∵-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