Question

若1/3a^3b^n和2a^m+1 b^3是同类项,且x+n的绝对值+(y-m)^2=0,求x^2-xy+2y^2的值

Answer 1

解 因为1/3a^3b^n和2a^m+1 b^3是同类项

所以 n=3 m+1=3 m=2

又IX+nI+(y-m)^2=0

所以x=-n=-3 m=y=2

x^2-xy+2y^2

=(-3)^2-(-3)*2+2*2^2

=9+6+8

=23