EXERCISES 14.4 Chain Rule: One Independent Variable In Exercises 1-6, (a) express dw/dt as a function of t, both by using the Chain Rule and by expressing w in terms of t and differentiating a directly with respect to t. Then (b) evaluate dw/dt at the given value of t. 1. w = x² + y², x = cost, y = sin t; t = π 2. w = x² + y², x = cost + sint, y = costsin t; t = 0 == y 3. w = +, x = cos²t, y = sin²t, z=1/t;_t=3 27 IN 4. w = In (x² + y²+ z²), x = cost, y = sint, z = 4√√t; t = 3