**1. The problem statement, all variables and given/known data**

The function

x = (7.4 m) cos[(5πrad/s)t + π/5 rad]

gives the simple harmonic motion of a body. At t = 6.2 s, what are the (a) displacement, (b) velocity, (c) acceleration, and (d) phase of the motion? Also, what are the (e) frequency and (f) period of the motion?

**2. Relevant equations**

**3. The attempt at a solution**

Hi! I understand that you’re supposed to plug in your t into the position function, and then take the derivative and continue plugging in. I think I’m messing up the math somehow because I keep getting the wrong answer…

(7.4)cos(98.0177)= -0.1395

http://ift.tt/1f5dHCY