Final answer:
The gradient vector ∇f of f(x,y) = xy² is (y², 2xy), and the derivative of the vector function r(t)=(1/2t²,t³) is r'(t) = (t, 3t²).
Step-by-step explanation:
The question involves calculus and vector analysis used to find the gradient vector (denoted as ∇f) of the function f(x,y) and the derivative of the vector-valued function r(t). To calculate these, we must use partial derivatives for ∇f and regular derivatives for r'(t).
To find the gradient of f(x,y) = xy², we take the partial derivatives with respect to x and y:
- ∇f = (∂f/∂x, ∂f/∂y) = (y², 2xy)
The derivative of r(t) is calculated by taking the derivative of each component:
- r'(t) = (d/dt (1/2t²), d/dt (t³)) = (t, 3t²)
Remember to perform the derivative operations according to the respective rules of differentiation.