I am asked to evaluate this combination of step functions, though I have no idea what to do with it. Anyone have any information on these types of problems or know what to do with it? x(t) = t^2.u(t) - t^2.u(t-1) + (t-2)^2.u(t-1) - u(t-3) Thanks.
As mik3 said, make a timeline and for each time sample (step) evaluate your function x(t) at that point.
Here's a python program that will evaluate the function if you think it's too much trouble to make a plot by hand: Code ( (Unknown Language)): from __future__ import division from pylab import * def function(t): u = lambda t: 1 if t >=0 else 0 return t**2*u(t) - t**2*u(t-1) + (t-2)**2*u(t-1) - u(t-3) n, a = 1000, 4 T, y = arange(-a, a, a/n), [] for t in T: y.append(function(t)) plot(T, y) grid(True) show() You'll need numpy and matplotlib to make the plot. u is the unit step function; there are different definitions floating around, so make sure you use the one your teacher wants you to use.