Question

先合并同列项,再求多项式的值 4m^2-4m+1-4+12m-9m^2,m=-1 (2)9x^2-12xy+4y^2,x

Answer 1

4m^2-4m+1-4+12m-9m^2,

=-5m^2+8m-3

=-5*1-1*8-3

=-16

9x^2-12xy+4y^2

=(3x-2y)^2

=(-1/2*3-2*1/2)^2

=(-5/2)^2

=25/4