Question

Anyone know this question?

Answer 1

`(f + g)(4) = 191`

Explanation:

Given

`f(x) = 5x^2 - 5x + 15`

`g(x) = 6x^2 + 7x - 8`

Required

`(f + g)(4)`

First, calculate
`(f + g)(x)`

This is calculated as:

`(f + g)(x) = f(x) + g(x)`

So, we have:

`(f + g)(x) = 5x^2 - 5x + 15+6x^2 + 7x - 8`

Collect like terms

`(f + g)(x) = 5x^2 +6x^2 - 5x+ 7x + 15 - 8`

`(f + g)(x) = 11x^2 + 2x + 7`

Substitute 4 for x

`(f + g)(4) = 11*4^2 + 2*4 + 7`

`(f + g)(4) = 191`