Question

You have to plug in (x+h) for x but im stuck

Answer 1

Explanation:

Given:
`f(x) = 2x^2 - 4x + 5`

`f(x + h) = 2(x+h)^2 - 4(x + h) + 5`

`\:\:\:\:\:\:\:\:=2(x^2 + 2hx + h^2) - 4(x + h) + 5`

`\:\:\:\:\:\:\:\:= 2x^2 + 4hx + 2h^2 - 4x - 4h + 5`

`(f(x + h) - f(x))/(h) = ((2x^2 + 4hx + 2h^2 - 4x - 4h + 5) - (2x^2 - 4x + 5))/(h)`

`= (4hx + 2h^2 - 4h)/(h) = 4x - 4 + 2h`