Hi Swathi,
this is almost certainly happening because sinh(z)/z = 1 at z=0, but sinh(z) and z when calculated separately and divided, gives 0/0 =nan. You need to create a function that calculates sinh(z)/z and replaces nan by 1 at z=0.
Incidentally you are missing dots at a couple of locations:
((sinh(x.*(aw/i).*sqrt(i/j)))./(x.*(aw/i).*sqrt(i/j)))
^
and similarly for the other sinh function. Of course this doesn't get you out of the nan problem, it just fixes up the element by element division.
