HP 48gII User Manual page 518

In this case, the period T, is 4. Make sure to change the value of variable
@@@T@@@ to 4 (use: 4 K @@@T@@ `). Function g(X) can be defined in the
calculator by using
DEFINE('g(X) = IFTE((X>1) AND (X<3),1,0)')
The function plotted as follows (horizontal range: 0 to 4, vertical range:0 to
1.2 ):
Using a procedure similar to that of the triangular shape in example 2, above,
you can find that
1
3
c 1 dX 0 5 .
,
0
T
1
and
π π
in /2 n 3in /2 n
We can simplify this expression by using e = i and e = (-i) to get:
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