# Evaluate integral at specific value

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Ahmed Abdulla on 7 Jun 2021
Answered: Walter Roberson on 7 Jun 2021
I have the following mathematical function f=5sin(x), I use the int(f) to obtain the integral of my expression. Is there a way for me to evaluate the result of the integral at a specifc value, lets say 4,32,
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Ahmed Abdulla on 7 Jun 2021
This substitutes x for a but doesnt evaluate the expression :(
Ahmed Abdulla on 7 Jun 2021
Thank you Salah, i combined your answer with vpa to evaluate:
vpa(subs(I,x,a))

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### Accepted Answer

Walter Roberson on 7 Jun 2021
syms x
f = 5*sin(x)
f =
fint = int(f,x,0,x)
fint =
a = 4.32
a = 4.3200
fa = subs(fint, x, a)
fa =
If you are expecting a decimal value, then you are wanting to get an approximation at the location, rather than the value at the location.
double(fa)
ans = 6.9120
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