Let f(x)=3x^3 +7.5x +1. In this problem you will estimate f'(3) by computing the average rate of change of f(x)over a small interval. Round your answers to three decimal places.

Question

Let f(x)=3x^3 +7.5x +1. In this problem you will estimate f'(3) by computing the average rate of change of f(x)over a small interval.  Round your answers to three decimal places.

First choose the interval of length .1 with 3 being the left endpoint of 
the interval. 
Then f'(3)≈ ______

Now let the interval have length .01. Then f'(3)≈ _______

Finally let the interval have length .001 
Then f'(3)≈

**I am genuinely lost on where to even begin with this problem. I understood the rest of my homework completely, except this one. My homework will be due before someone can get to answer this, I am almost sure of that, so please - just work it out for me so that I can better understand it for the midterm.