Question

solve please c part by using Formula a²+2ab+b²

Answer 1

2 should be added as
$(a {}^{2} + \frac{1}{a {}^{2} } ) {}^{2} = {a}^{4} + \frac{1}{ {a}^{4} } + 2 \times {a}^{2} \times \frac{1}{a {}^{2} }$
now a^2 cancel each other so
2 should be added