The position of a an air-track cart that is oscillating on a spring is given by (12.5cm)cos[(18.0s-1)t].
At what value t after t=0 is the cart first located at x=12.2 cm?
The Attempt at a Solution
12.2 cm = (12.5cm)cos[(18.0s^-1)t].
How do I factor t out?