# Math Help - Derivative by first principles

1. ## Derivative by first principles

I know how to do the question, I am just having trouble with the algebra someone please help

2. ## Re: Derivative by first principles

Please show us what you have done, then we can guide you wherever you made a mistake or are stuck.

3. ## Re: Derivative by first principles

I can't quite read the numerator of your function. They mean for you to plug in to the definition of derivative: $f'(x)=\lim_{h\to{0}}\frac{f(x+h)-f(x)}{h}$.

So what happens when you plug in your function?

- Hollywood

4. ## Re: Derivative by first principles

It's ok I got it, someone helped me out