MATLAB: How to solve exponential distribution equation using symbolic Matlab

integrationsymbolicSymbolic Math Toolbox

I have exponential distribution function – F(tau) = beta * e^(-beta*tau). I need to integrate tau*F(tau) over the intervall 0 to inf, My answer should be 1/beta, however I don't get this answer. This is what I did:

>> syms tau beta

>> home

>> syms tau beta

>> f = tau*beta*exp(-beta*tau);

>> int(f, tau)

ans =

-(exp(-beta*tau)*(beta*tau + 1))/beta

Thanks for help, in advance.

Best Answer

It helps the int if you explicitly tells what the range to integrate over is:

int(f,0,inf)

HTH

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This now does not throw an error

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It is the correct result, it is just a different way of writing it.

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