The length of a rectangle is increasing at while its width is decreasing at

MATHEMATICS · Single correct · AP · Calculus AB · Contextual Applications of Differentiation · Contextual Applications of Differentiation

Problem

The length of a rectangle is increasing at

3\,\text{cm/s}

while its width is decreasing at

3\,\text{cm/s}

. What is the instantaneous rate of change of its perimeter? (a)

12\,\text{cm/s}

(b)

0\,\text{cm/s}

(c)

6\,\text{cm/s}

(d)

-6\,\text{cm/s}