Question

How do you factor the expression `9x^3 + 18x^2 + 7x + 14`?

Answer 1

`(x +2)(9x^2 + 7)`

Explanation:

'split' the expression into two groups

so [`9x^3 + 18x^2 ] + [ 7x + 14 ]`

now factorise each group

`9x^3+18x^2 = 9x^2(x+2) " and " 7x+14= 7(x+2)`

there is now a common factor of (x+2) in each pair

`rArr 9x^3+18x^2+7x+14 = (x+2)(9x^2+7)`