A particle’s position is for

MATHEMATICS · Subjective · AP · Calculus BC · Parametric, Polar, and Vector-Valued Functions · Parametric, Polar, and Vector-Valued Functions

Problem

A particle’s position is

\mathbf r(t)=\langle\sin t,\;\cos 2t\rangle

for

0\le t\le2\pi

. List all values of

t

in this interval where the particle changes vertical direction.