A 15-ft ladder rests against a vertical wall

MATHEMATICS · Subjective · AP · Calculus AB · Contextual Applications of Differentiation · Contextual Applications of Differentiation

Problem

A 15-ft ladder rests against a vertical wall, making an angle

\theta

with the ground. The foot of the ladder begins to slide directly away from the wall. At that instant, is

\frac{d\theta}{dt}

positive, negative, or zero? Briefly justify your answer.