Question

this is the expansion formulae and slove with (a+b)(a-b)=a²+a-b²​

Answer 1

Step-by-step explanation:

$(x + \frac{1}{x} )(x - \frac{1}{x} ) \\ \\ \\ = {x}^{2} - \frac{1}{ {x}^{2} } \\ \\ \\ = {x}^{4} - 1$

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