Consider F and C below. F(x, y, z) = yzexi + e*%j + xyek, C: r(t) = (t? + 2)i + (t2 - 1)j + (42 - 3t)k, Osts 3 (a) Find a function f such that F = Vf. f(x, y, z) = (b) Use part (a) to evaluate be F. d