integral does not give results

x=sym('x')

int(((x*exp(-x/3))+tan(x)),0,5)

I can't find where I made the mistake, Matlab does not give results

Answer 1

[Star Strider]

It works for me (in R2020a):

x=sym('x')
Int = int(x*exp(-x/3)+tan(x),x,0,5)

producing:

Int =
NaN

To understand the results, plot the function:

figure
fplot(x*exp(-x/3)+tan(x), [0,5])
grid

.

[Bilal Ates]

x=sym('x')

int(((x*exp(-x/3))),0,5) + int(tan(x),0,pi/36)

it worked...

[Star Strider]

That is not the same as in your original Question.

[Bilal Ates]

tan (x) gives an error, isn't it true?

[Star Strider]

It gives NaN (in R2020a) when evaluated across . or any other angle x where .

syms x 
I = int(tan(x), 0, 5)

produces:

I =
NaN

It may give different results in other versions.

.

[Bilal Ates]

Thank you sur

[Star Strider]

My pleasure!

[Bruno Luong]

This might be useful

syms x
Int = int(x*exp(-x/3)+tan(x),x,0,5,'PrincipalValue',true)