Solving an integral with limits being a vector

Hi,

I'm trying to solve an equation that holds an integral in it. In that equation there are several constants and I would like to solve this for different values of that constants. However, it gives an error as "this value must be real". I've tried to sum up my problem if it is not clear i will glad to explain and get some help.

Mathcad file is attached.

Thanks

Burak