Question

Factorise completely:
4p2 - 9

Answer 1

4 ( P - 3/2) ( P + 3/2)

First is to divide through the equation by 4

4 ( P^2 + 9/4)

Secondly, Replace the 9/4 with (3/2)^2

Thirdly, Use the difference of square for the first step equation

a^2 - b^2 = (a - b) (a + b)

Applying the above equation to the second step taken we have

4 ( P^2 - (3/2)^2)

4 ( P - 3/2) ( P + 3/2).