How to create a Sawtooth Wave program AND modify a Noise file to create a Square Wave in MATLAB?

Part 1

I know the formula for a Sawtooth Wave from my Calc 2 course (sorry for the vague format):

f(t) = A/2 - A/pi * Sigma (sin(pi*k*t/T)*(-1)^k)/k

Steps to follow:

1. A conventional sawtooth can be constructed using the series formula above

2. Write a program which will plot the first 40 terms in the sawtooth series

3. Set the period (T) to 1 – but calculate the time vector to run from -2*T to +2*T

4. Set the Amplitude (A) to 4

Part 2

modify the program to create a square wave that has a period (T) of 5 seconds) and multiply the noise by the square wave before adding it to the sound