MATHEMATICS · Single correct · AP · Calculus BC · Parametric, Polar, and Vector-Valued Functions · Parametric, Polar, and Vector-Valued Functions
Problem
In the study of parametric curves, the condition f′(t)=0 is imposed mainly because it
(a) to ensure that dtdy exists
(b) to guarantee that x=f(t) is monotonic throughout the interval
(c) to prevent division by zero when forming dxdy
(d) to avoid sharp cusps by forcing the curvature to vanish