Finding total energy of an oscillator

[jca90]

Homework Statement

Find the total energy of the following (mass m= 2 kg) oscillator.

Homework Equations

x=2cos(6∏t)

The Attempt at a Solution

Wouldn't I take my Amplitude of 2 and my period of 6 mulitply them together to get my max velocity of 12 then using KE = 1/2msquared I would take 1/2(2)(12)squared to get 144. But this is no where close to being right. My choice are:

A) 1320
B) 1420
C) 1520
D) 1620
E) 1720
F) 1820

 

[ehild]

The simple harmonic motion is described with a function x(t)=Acos(ωt), with ω the angular frequency. The maximum speed is v(max)=Aω. You need ω. What is it if x(t)=2cos(6π t)?

ehild