Final answer:
The derivative of 4 cos(x) sin(y) = 1 is -4 sin(x) sin(y) with respect to x and 4 cos(x) cos(y) with respect to y.
Step-by-step explanation:
To find the derivative of 4 cos(x) sin(y) = 1, we need to differentiate each term with respect to x and y separately using the product rule.
Derivative with respect to x:
d/dx(4 cos(x) sin(y)) = -4 sin(x) sin(y)
Derivative with respect to y:
d/dy(4 cos(x) sin(y)) = 4 cos(x) cos(y)
Therefore, the derivative of 4 cos(x) sin(y) = 1 with respect to x is -4 sin(x) sin(y) and with respect to y is 4 cos(x) cos(y).