Question

Please give your answer in step by step explanation of this expansion = -2?​

Answer 1

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$(a - \frac{1}{a} ) ^{2} \\ = > {a}^{2} + \frac{1}{ {a}^{2} } - 2 \times a \times \frac{1}{a} \\ = > {a}^{2} + \frac{1}{ {a}^{2} } - 2$

hope it helps... :)