Question

3a^7b-81a^4b^4 factorise

Answer 1

The answer is given below :

Now,

$3 {a}^{7} b - 81 {a}^{4} {b}^{4} \\ \\ = 3ab( {a}^{6} - 27 {a}^{3} {b}^{3} ) \\ \\ = 3ab( { {(a}^{2} )}^{3} - { {(3ab)}^{3} }) \\ \\ = 3ab( {a}^{2} - 3ab)( {( {a}^{2}) }^{2} + ( {a}^{2} \times 3ab) + {(3ab)}^{2} ) \\ \\ = 3ab( {a}^{2} - 3ab)( {a}^{4} + 3 {a}^{3} b + 9 {a}^{2} {b}^{2} )$

which is the required factorization.

Thank you for your question.

Answer 2

Hey.Here is your answer u r looking for..

See the attachment