Mathematics

Problem

A particle moves on a line with velocity

v(t)=(t-2)^{2}(t+1)

meters per second. At which of the following times is the particle at rest but does NOT change direction? a) Both

t=-1\text{ s}

and

t=2\text{ s}

t=-1\text{ s}

t=2\text{ s}

d) Neither

t=-1\text{ s}

nor

t=2\text{ s}