14.5 Partial Derivatives 12) Use the Chain Rule to find Oz/as and Oz/at. z = tan (x2 +y?), x =slut, y=te: 28 Use the Chain Rule to find the indicated partial derivatives. P= Vultur+w2, u=me", v = yet , w = exy; ap ap Ox' dy when x = 0, y = 2 34 Use Equation 5 to find dy / due. 5 OF dy OF = - dac ay ey sin x = x + cy 49 49. If z = f (x, y), where z = rcos 0 and y = rsin 0, a. find az/Or and Oz/20 and Answer + az/Or = (Oz/8x) cos 0 + (Oz/dy) sin 0, Oz/80 = - (Oz/Ox) r sin 0 + (Oz/dy) r cos 0 b. show that 55 If z = f (x, y), where x = rcos 0 and y = r sin 0, show that 1 oz ay 2 72 202