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Hi,
This thread is an extension of this discussion where @DrClaude helped me. I thought that it'd be better to separate this question.
I couldn't find any other way to post my work other than as images so if any of the embedded images are not clear, just click on them. It'd make them clearer. I'd really appreciate if you can help me.
Original expression:
Laplace transform of the expression:
The graph of the expression is shown below.
High res image for the above embedded image: https://imagizer.imageshack.com/img924/2191/JaiscO.jpg
High res image for the above embedded image: https://imagizer.imageshack.com/img921/3007/iPI3pi.jpg
Sadly there is something wrong and I'm not getting the original f(t)=1(1/3)e^(t)sin(3t)e^(t)cos(3t). Please see the plot below. Where am I going wrong?
This thread is an extension of this discussion where @DrClaude helped me. I thought that it'd be better to separate this question.
I couldn't find any other way to post my work other than as images so if any of the embedded images are not clear, just click on them. It'd make them clearer. I'd really appreciate if you can help me.
Original expression:
Laplace transform of the expression:
The graph of the expression is shown below.
High res image for the above embedded image: https://imagizer.imageshack.com/img924/2191/JaiscO.jpg
High res image for the above embedded image: https://imagizer.imageshack.com/img921/3007/iPI3pi.jpg
Matlab:
clear all; close all; clc;
sig=1;
b=2;
t=linspace(0,30,3000);
for it=1:3000 %index for t varible
[email protected](w)(1/pi).*(((10.*(sig.^3sig.*w.^2+b.*sig.^2+10.*sig2.*sig.*w.^2b.*w.^2))/(sqrt(w.^6+w.^4.*(b.^2+2.*b.*sig+3.*sig.^220)+w.^2.*(2.*b.^2.*sig.^2+4.*b.*sig.*(sig.^2+5)+3.*sig.^4+100)+(b.^2.*sig.^2+2.*b.*sig.*(sig.^2+10)+sig.^4+20.*sig.^2+100).*sig^2))).*cos(w.*t(it))+(10.*(2.*sig.^2.*w+sig.*b.*w+w.*sig.^2w.^3+b.*sig.*w+10.*w)/(sqrt(w.^6+w.^4.*(b.^2+2.*b.*sig+3.*sig.^220)+w.^2.*(2.*b.^2.*sig.^2+4.*b.*sig.*(sig.^2+5)+3.*sig.^4+100)+(b.^2*sig.^2+2.*b.*sig.*(sig.^2+10)+sig.^4+20.*sig.^2+100).*sig.^2))).*sin(w.*t(it)));
F(it)=integral(f,0,100); %evaluating the integral from w=0 to w=100
end
plot(F) % F is inverse Fourier transform of f(t)
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