Question

Factorise fully

16(a+b)(a+b)-1
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Answer 1

(4a +4b +1)(4a+4b -1)

Explanation:

Identity: (x + y)(x - y) =x² - y²

16 (a + b)(a + b) - 1 = 4²*(a+b)² - 1

= [4(a+b)]² - 1²

Here, x = 4(a+b) and y = 1

= [4(a+b) -1] [4(a+b) + 1]

= [4a+4b - 1] [4a+ 4b + 1]