Evaluate Finite Difference Approximations in C

# Introduction

In this lab, you will learn how to evaluate finite difference approximations of derivatives in C. The lab covers the following steps:

1. Define a mathematical function `f(x)` and set up the step size `h` for finite difference approximations.
2. Compute forward and backward finite difference approximations of the derivative of `f(x)` at a given evaluation point `x`.
3. Print the computed approximations and compare them to the true derivative.

By the end of this lab, you will have a solid understanding of how to implement finite difference methods in C and assess the accuracy of the approximations.