Let C be the curve of intersection of the parabolic cylinder z? = 2y and the surface 3z = xy. Find the exact length of C from the origin to the point (6, 18, 36). Answer + 42 Find the curvature of r(t) = (t2, In t, t In t) at the point (1, 0, 0). Use Theorem 15 to find the torsion of the given curve at a general point and at the point corresponding to t = 0. W 15 Theorem The torsion of the curve given by the vector function r is T (t ) = [r' (t) *r" (t) ]'r' (t) |r' (t ) I" (t) 1 2