Question

plz solve this issue with regard

Answer 1

$(m + \frac{n}{7} ) ^{3} (m - \frac{n}{7} ) \\ = (m + \frac{n}{7} ) ^{2} (m + \frac{n}{7} )(m - \frac{n}{7} ) \\ = (m + \frac{n}{7} ) ^{2} (m - \frac{n}{7} ) ^{2} \\ = ((m + \frac{n}{7} )(m - \frac{n}{7} )) ^{2} \\ = ( {m}^{2} - \frac{n}{7} ^{2} )^{2}$
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