I couldn't able to get this solved by Mathcad.
Can anyone explain to me why?
there are 2 problems:
the first is that you are trying to calculate tan^2 multiplied by(x)
this should look like
the second is that the tan function is discontinuous over the range that you have specified
you don't specify what the numbers a and b are, Mathcad default is the arguments to trig functions are in radians.
If you are wanting them to be in degrees then you can change the definitions for a and b to
and this allows the integral to converge.
Hope this helps
It really helps a lot!
Thank you for spending your precious time to explain.