Factorize:

We know that,


a3 - b3 = (a - b) (a2 + a × b + b2)


Using this formula, we get


= a3 - 1/a3 – 2 (a – 1/a)


= (a – 1/a) (a2 + a × 1/a + 1/a2) – 2 (a – 1/a)


= (a – 1/a) (a2 + 1 + 1/a2 – 2)


=


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