Question

PRECALC./TRIG QUESTION: The shaft on the pedal of a bicycle is 7 inches long and attaches to the bicycle 11 inches off of the ground. If the pedal starts in the standard (3.00) position, and rotates counterclockwise, write an equation that can model the height of the pedal off of the ground based on the number of radians that it has been rotated

Answer 1

The height of the pedal off the ground can be modeled by a cosine function

`h(\theta)=\text{ 18 - 7}\cos (\theta+(\pi)/(2))`

Let, us try some scenarios, if the pedal is at the 3 oclock position, the angle = 0

h= 18-7cos90 = 18 - 0 = 18 inches.

If the pedal is at 12 oclock, the angle is pi/2 or 90 degrees, and

h= 18 - 7cos180 = 18+7 = 25 inches.