Qual a derivada parcial de fy se f(x,y) = y.senxy?

F(x,y) =y * sen(xy)

fy = (y)' * sen(xy) + y * (sen(xy))'

fy= 1 * sen(xy) + y * (xy)' * cos(xy)

fy= 1 * sen(xy) + y * x * cos(xy)

fy= sen(xy) +yx *cos(xy)