Question

Qual o valor de a²+ 2ab, para a=-1 e b= 2?

a) 5

b) -4

c) -3

d) 2

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Answer 1

$\mathsf{{a}^{2}+2ab\big|_{a=-1\,b=2}}$

$\large\mathsf{{(-1)}^{2}+2.(-1).2=1-4=-3}$