0
$\begingroup$

I observe that if I execute in the url of wolfram alpha the integral of the function (3/x^2)Sin(x)Sin(x/3) with the limits between zero and infinity:

integrate (3/x^2)sin(x)sin(x/3) from 0 to inf

I get a correct PI/2 value, but if I do it on my computer with my Mathematica, it does not return anything, as a result shows me the same integral.

Integrate [(3 / x ^ 2) Sin[x] Sin[x / 3], {x, 0, inf}]

Why? Is it because my computer?

Thank you

Improve this question
$\endgroup$
1
  • $\begingroup$ Syntax error: infinity is represented as Infinity, not inf. $\endgroup$ Commented Aug 25, 2017 at 8:15

1 Answer 1

Reset to default
1
$\begingroup$

You should use Infinity rather than inf.

Integrate[(3/x^2) Sin[x] Sin[x/3], {x, 0, Infinity}]
 π/2
Improve this answer
$\endgroup$
1
  • $\begingroup$ Thank you very much; I had try with inf and with the symbol; I will try with infinity. $\endgroup$ Commented Aug 25, 2017 at 8:26

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.