If
\[
f(x,y,z)=e^{\,1-y\cos x}+yze^{\frac{-1}{1+x^2}},
\]
then
\[
\frac{\partial f}{\partial y}
\]
at \((0,1,e)\) is
Show Hint
When evaluating a partial derivative at a point, first differentiate symbolically and then substitute the coordinates. This minimizes computational errors.