HP 33s - Manual (Page 123)

Integrating Equations 8–1
8
Integrating Equations
Many problems in mathematics, science, and engineering require calculating the
definite integral of a function. If the function is denoted by f(x) and the interval of
integration is a to b, then the integral can be expressed mathematically as
³
=
b
a
dx (x) f I
f (x)
b
x
a
I
The quantity I can be interpreted geometrically as the area of a region bounded by
the graph of the function f(x), the x–axis, and the limits x = a and x = b (provided
that f(x) is nonnegative throughout the interval of integration).
The  operation ( ³ FN) integrates the current equation with respect to a
specified variable ( ³  d_). The function may have more than one variable.
 works only with real numbers.