Question

a body oscillates with s.h.m according to the equation x=(6.12)cos[(8.38rad/sec)+1.92rad] find a)displasement b)velocity c)acceleration at the time t=1.90s.find also d)the frequency and e)period of the motion.

Answer 1

First, I think you left the t out of the equation by accident. It should be:
\[x=6.12cos(8.38t+1.92)\]

For a), just do that sum with t=1.9. x is the displacement.
For b), you have to know that velocity is the time-derivative of displacement, i.e. \[v=\frac{dx}{dt}\]
So if you differentiate that first equation for x with respect to t, you'll have an equation for velocity. Then just evaluate it at t=1.9.
For c), you have to know that \[a=\frac{dv}{dt}=\frac{d^2x}{dt^2}\]
So you have to do something similar to b).
For d), I'll tell you that one of the numbers in the original equation for x you have is the ANGULAR frequency, which is 2π times the frequency. Which one do you think it is?
For e), f=1/T

Answer 2

un cuerpo oscila con m.a.s con una elongacion x=6.12 cos(8.38t + 1.92) con x en metros y t en segundos.
1. el valor de elongacion cuando t= 1.90 s ¿es?

Answer 3

cual es el procedimiento