Factorize:

3a3b – 243ab3

We have,



= 3ab(a2 – 81b2)


We can also write the expression as:


= 3ab[(a)2 – (9b)2]


Now,


Using identity: a2 – b2 = (a – b)(a + b)



Hence,


The given expression can be factorized as:


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