1. The problem statement, all variables and given/known data The position of a particle is given in cm by x = 6*cos(3πt), where t is in seconds. What is the first time that the particle is at x = 0 and moving in the +x direction? 2. Relevant equations 3. The attempt at a solution I set x=0, and divided 0 by 6, resulting in 0. From there, I took the inverse cosine of each side, leaving me with the equation (π/2)=3πt. Then I divided (π/2) by 3π, and was left with a t value of .13351 seconds. The problem is that when I submit that answer, it is incorrect.