(a+b)(3a-b) a=(2;-1;0) b=(4;5;7)

Question

(a+b)(3a-b)
a=(2;-1;0)
b=(4;5;7)

Answer 1

1)3a^2+3ab-b^2=6^2+11-4^2=47-64=(-17)
2)3a^2+3ab-b^2=(-3)^2+-15-5^2=9-40=(-31)
3)3a^2+3ab-b^2=0-7+49=42