Question

20. If a = 2, b = (-2), find the value of a2 + ab + b2​

Answer 1

Answer:

$(a + b)^{2} = \: {a}^{2} + 2ab + {b}^{2} \\ substuting \: values \: given \\ \\ (2 + ( - 2))^{2} = {2}^{2} + 2 \times 2 \times ( - 2) + { ( - 2)}^{2} \\ \\ {(2 - 2)}^{2} = 4 + ( - 8) + 4 \\ \\ {0}^{2} = 8 - 8 \\ \\ 0 = 0 \\ \\ therefore \: answer \: is \: zero$

Answer 2

Answer:

a= 2, b=-2

2a+ab+2b

=2×2+2×(-2) +2×(-2)

=4+(-4) +(-4)

=4-4-4

= -4 ans.