Question

Factorise the following:

(a + b)² – 9

Answer 1

Given:

(a + b)² – 9

Step-wise calculation:

1. Recognize the expression as a difference of squares:

(a + b)² – 3²

2. Apply the difference of squares identity:

x² – y² = (x + y)(x – y) where x = a + b and y = 3.

3. So, (a + b)² – 9 = (a + b + 3)(a + b – 3).