A particle moves according to for

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

Problem

A particle moves according to

\mathbf r(t)=\langle \sqrt{t+1},\, \ln (t+2) \rangle

for

t\ge -1

. What is the particle’s speed at

t=0

? (a)

1

(b)

\dfrac{\sqrt5}{2}

(c)

\dfrac{\sqrt2}{2}

(d)

\dfrac12