Problem 3. Textbook problem 2.3. Suggested steps to solve: (1) Rewrite the left-hand side of this equation with the first velocity vector expanded into its x,y, and z magnitude and unit-direction vectors while leaving the second velocity vector as is (i.e., don't expand it into its x,y, and z components). (2) Do the dot product, which is between the gradient operator and the first velocity vector. (3) Use the chain rule of differentiation to further expand each term (e.g., x(ab)=bx(a)+ax(b)). (4) Recombine terms and condense the math to match the terms on the right-hand side of the equation given in the problem, thus proving the relationship