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HP 50g Graphing Calculator User Manual

Page 521

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Page 16-44

and

The continuous spectrum is given by

The functions C(

ω), S(ω), and A(ω) are continuous functions of a variable ω,

which becomes the transform variable for the Fourier transforms defined below.

Example 1 – Determine the coefficients C(

ω), S(ω), and the continuous spectrum

A(

ω), for the function f(x) = exp(-x), for x > 0, and f(x) = 0, x < 0.

In the calculator, set up and evaluate the following integrals to calculate C(

ω)

and S(

ω), respectively. CAS modes are set to Exact and Real.

Their results are, respectively:

The continuous spectrum, A(

ω) is calculated as:

.

)

sin(

)

(

2

1

)

(

−∞

=

dx

x

x

f

S

ω

π

ω

2

2

)]

(

[

)]

(

[

)

(

ω

ω

ω

S

C

A

+

=