Fourier series of periodic function

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Homework Help Overview

The discussion revolves around the Fourier series of a periodic function defined piecewise. The function takes the value of 0 for certain intervals and 1 for another, with a specified period. Participants are tasked with graphing the function and calculating its Fourier series coefficients.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • Participants are discussing the definition of the period (P) and the half-period (L) in relation to the Fourier series. There are questions about the correct value of L and its implications for the calculations. Some participants are verifying the accuracy of their graphs and calculations.

Discussion Status

Some guidance has been provided regarding the graph's accuracy, and there is ongoing clarification about the definitions of P and L. Multiple interpretations of L are being explored, but no consensus has been reached on the correct approach to the Fourier series coefficients.

Contextual Notes

There is ambiguity regarding the definitions of P and L, which are crucial for the Fourier series calculations. Participants are working with a piecewise function and have referenced an attached file for the graph, which is not visible in the discussion.

masterchiefo
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Homework Statement


Periodic function P=3
f(t) = 0 if 0<t<1
1 if 1<t<2
0 if 2<t<3
a) Draw the graph of the function in the interval of [-3,6]

b) Calculate the Fourier series of f(x) by calculating the coefficient.

Homework Equations

The Attempt at a Solution


a) in attached file

b)
How do I know what is my L?
L=3/2## \text{ao} = \frac1L \int_0^{3} \left( f(x) \right) dx ##
## \text{ao} = \frac1L \int_0^{1} \left( 0 \right) dx + \frac11 \int_1^{2} \left( 1 \right) dx + \frac11 \int_2^{3} \left( 0 \right) dx ##
ao=2/3

## \text{an} = \frac1L \int_1^{2} \left( 1cos(n*pi)/L*x) \right) dx ## n>=1
an= sin(2*n*pi)/n*pi -sin(n*pi)/n*pi

## \text{an} = \frac1L \int_1^{2} \left( 1sin((n*pi)/L*x) \right) dx ## n>=1
bn= cos(n*pi)/n*pi - cos(2*n*pi)/n*pi
 

Attachments

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masterchiefo said:

Homework Statement


Periodic function P=3
f(t) = 0 if 0<t<1
1 if 1<t<2
0 if 2<t<3
a) Draw the graph of the function in the interval of [-3,6]

b) Calculate the Fourier series of f(x) by calculating the coefficient.

Homework Equations

The Attempt at a Solution


a) in attached file

b)
How do I know what is my L?
L=1

You haven't told us what P is. I suppose it is the period. If so, the P = 3. You also haven't told us what L is defined as. Is it half the period? If so then L = 3/2.
 
LCKurtz said:
You haven't told us what P is. I suppose it is the period. If so, the P = 3. You also haven't told us what L is defined as. Is it half the period? If so then L = 3/2.
okay, after I change L for the correct value, is the steps good ?
is my graph good ?
 
Your graph is good. I didn't check your arithmetic.
 

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