Question

factorize a (a-1) - b (b-1)​

Answer 1

As we know that

a

2

−b

2

=(a+b)(a−b)

a(a−1)−b(b−1)=a

2

−a−b

2

+b

=a

2

−b

2

−a+b

=(a−b)(a+b)−(a−b)

=(a−b)(a+b−1)