Factorize:

(a + b)3 – a – b

We have,



= (a + b)3 – (a + b)


= (a + b) [(a + b)2 – 1]


We can also write the expression as:


= (a + b)[(a + b)2 – (1)2]


Now,


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



Hence,


The given expression can be factorized as:


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