Question

Expand using appropriate identities:

(2m + n)(2m +p)

Answer 1

(2m + n) (2m + p)

Comparing (2m + n) (2m + p) with (x + a) (x + b) we have x = 2n; a = n ;b = p

(x – a)(x + b) = x² + (a + b)x + ab

(2m +n) (2m +p) 

= (2m²) + (n +p)(2m) + (n) (p)

= 2²m² + n(2m) + p(2m) + np

= 4m² + 2mn + 2mp + np