Question

Mark the correct alternative in the following question:

The sum of the values of the expression 2x² + 2x + 2 when x = $-$1 and x = 1 is
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(a) 6 (b) 8 (c) 4 (d) 2

Answer 1

Since, when x = $-$1, the value of the expression 2x² + 2x + 2 = 2($-$1)² + 2($-$1) + 2 = 2 $-$ 2 + 2 = 2

And, when x = 1, the value of the expression 2x² + 2x + 2 = 2(1)² + 2(1) + 2 = 2 + 2 + 2 = 6

So, the sum of the values of the expression 2x² + 2x + 2 when x = $-$1 and x = 1 = 2 + 6 = 8

Hence, the correct alternative is option (b).