(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The motion of a particle is described by the position function

s=((1/3)t^3)-(29t) - (1296/t), t>=1,

where t is the time in seconds and s is the displacement in metres

a) What is the velocity when acceleration is zero?

b) Find the displacement when v = 68m/s

c) When is the acceleration -90m/s^2?

2. Relevant equations

3. The attempt at a solution

a) Well, if the velocity is ((t^2)-(29)+(1296t^-2), and the acceleration is (2t^4 - 2592)/t^3, then wouldn't the velocity be 0 when acceleration is 0?

b) v(68)= 4595

c)-90 = (2t^4 - 2592)/t^3 ? (Doesnt seem to work)

I know Im doing something terribly wrong

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# Homework Help: Position functions

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