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math121a-f23:hw_8

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math121a-f23:hw_8 [2023/10/20 22:06]
pzhou
math121a-f23:hw_8 [2023/10/24 21:43] (current)
pzhou
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 Suppose you are given a function on an interval, f(x):[0,1]Rf(x): [0, 1] \to \R. Such function f(x)f(x) can be expressed as a sum of 'sine waves' and cosine waves and constant Suppose you are given a function on an interval, f(x):[0,1]Rf(x): [0, 1] \to \R. Such function f(x)f(x) can be expressed as a sum of 'sine waves' and cosine waves and constant
  
- f(x) = a_0 + \sum_{n=1}^\infty a_n \cos(\pi x) + b_n \sin(\pi x). + f(x) = a_0 + \sum_{n=1}^\infty a_n \cos(2n \pi x) + b_n \sin(2n \pi x).
  
 Can you figure out a way to determine the coefficients ana_n and bnb_n Can you figure out a way to determine the coefficients ana_n and bnb_n
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  f(x) = \begin{cases} 1 & 0 < x < 1/2 \cr  f(x) = \begin{cases} 1 & 0 < x < 1/2 \cr
 0 & 1/2 \leq x \leq 1  0 & 1/2 \leq x \leq 1 
-\end{\cases}+\end{cases} 
 + 
 find a0,a1,b1a_0, a_1, b_1 and plot the truncated Fourier series find a0,a1,b1a_0, a_1, b_1 and plot the truncated Fourier series
-a0+a1cos(πx)+b1sin(πx). a_0 + a_1 \cos(\pi x) + b_1 \sin(\pi x).  + a_0 + a_1 \cos(\pi x) + b_1 \sin(\pi x).  
-How does the resemble your original given function? +How does this resemble your original given function? 
  
    
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 And suppose f(0)=1f(0) = 1. Can you solve f(t)f(t) for t>0t > 0 And suppose f(0)=1f(0) = 1. Can you solve f(t)f(t) for t>0t > 0
  
-For the following problems, you need to apply Laplace transformation to the equation, and get the F(p)F(p) for the desired f(t)f(t), and do the inverse Laplace transformation to get back the desired answer.  
  
 3. Consider the following equation, for t>0t>0, 3. Consider the following equation, for t>0t>0,
math121a-f23/hw_8.1697864819.txt.gz · Last modified: 2023/10/20 22:06 by pzhou