Question

What is `int -sinx^2/x^2`?

Answer 1

`int sinu/u du` is what Wolfram Alpha calls the Sine Integral (denoted `Si`). It is not usually studied in introductory calculus courses.

Explanation:

You can read more about it here: http://functions.wolfram.com/GammaBetaErf/SinIntegral/

and here http://reference.wolfram.com/language/ref/SinIntegral.html

and here
http://reference.wolfram.com/language/ref/SinIntegral.html