Question

Factorise a^7 - ab^-6

Answer 1

${a}^{7} - {ab}^{ - 6} \\ a( {a}^{6} - {b}^{ - 6} ) \\ { {(a}^{3} )}^{2} - { (\frac{1}{ {b}^{ 3} } })^{2} \\ ( {a}^{3} + \frac{1}{ {b}^{3} } )( {a}^{3} - \frac{1}{ {b}^{3} } ) \\ (a + b) ( {a}^{2} - \frac{a}{b} + \frac{1}{ {b}^{2} } )(a - b)( {a}^{2} + \frac{a}{b} + \frac{1}{ {b}^{2} } )$
hope this helps u