Consider the helix [math]H(t) = (\cos t, \sin t, t)[/math]. Find the normal planes at two points time [math]t=a[/math] and a slightly later time [math]t=b[/math]. Find a vector to describe the direction of the line of intersection and use this vector to find the osculating plane.

Emma Phillips[br]October 2015[br]Phillips Exeter Academy