(2) If X=-2 and X=I are brought into 2x 4-4x 3+ax 2+7x+b respectively, there are

32+32+4A- 14+B=0

2-4+A+7+B=0。 Simplify these two equations and get.

4A+B+50=0

A+B+5=0 Solve this binary linear equation and get A=-15 B= 10.