dear,
first consider dy/dx = sinpx.cospy
i.e. secpy dy = sinpx dx
integrating both sides
we get,
log(secpy+tanpy)/p = -cospx/p
or log(secpy+tanpy)=-cospx
now you take dy/dx=p+cospxsiny=p-(-cospx)(siny)
putting the value of (-cos x) in the above equation,
dy/dx=p-log(secpy+tanpy)(siny)
i.e. dy/(p-log(secy+tany)(siny))=dx
now integrate both sides
and get your answer.
if you will not be able to integrate i will solveit for you.