Q66 of 100 Page 312

Find the values of the following polynomials at a = – 2 and b = 3:

(a) a2 + 2ab + b2


(b) a2 – 2ab + b2


(c) a3 + 3a2b + 3ab2 + b3


(d) a3 – 3a2b + 3ab2 – b3


(e)


(f)


(g)


(h) a2 + b2 – ab – b2 – a2

(a) a2 + 2ab + b2


(-2)2 + 2(-2)(3) + (3)2


= 1


(b) (-2)2 – 2(-2)(3) + (3)2


= 25


(c) (-2)3 + 3(-2)2(3) + 3(-2)(3)2 + (3)3


= 1


(d) (-2)3 – 3(-2)2(3) + 3(-2)(3)2 – (3)3


= -125


(e)


=


(f)


=


(g)


=


(h) (-2)2 + (3)2 – (-2)(3) – (3)2 – (-2)2


= 6


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