Question

已知Ia-2I+(b+1)=0求5ab^2-{2a^b-[3ab^2-(4ab^2-2a^2b)]}的值

Answer 1

2(a-2)^2 (b 1)^2=0,

a-2=0 a=2

b 1=0 b=-1

3a^2 b ab^2-3a^2 b 5ab ab^2-4ab 1/2a^2b

=1/2a^2b 2ab^2 ab

=1/2x4x-1 2x2x1 2x-1

=-2 4-2

=0