A differentiable vector-valued function satisfies

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

Problem

A differentiable vector-valued function

r(t)

satisfies

|r(t)| = c

, where

c

is a non-zero constant. Show that

r(t)

is orthogonal to

r'(t)

for every

t