Tutorial to explore and understand what is a periodicfunction. Before you start the tutorial, let us review the definition of a periodic function.
A function f is periodic with period P if
f(x) = f(x + P) , P is a real number.
The graph of a periodic function repeats itself indefinitely. If f is known over one period, it is known everywhere since the graph repeats itself.
Interactive Tutorial
1  click on the button above "click here to start" and MAXIMIZE the window obtained.
2  Use the top slider (Change shape) to change the shape of the graph of function f.
3  Use the middle slider (Change period) to change the period of function f.
4  Use the bottom slider( shift ), start from the left when P = 0 and change P slowly shifting the graph of f. When the graph of f in blue ( f(x) ) and the graph in red ( f(x + P) ) are identical ( superimposed ), the value of P displayed (as a multiple of Pi) is an approximation to the period of the graph of f.
5  Change the shape and period and repeat the above exploration.
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