A particle moves along a line so that its position at any time t>0 is given by the funciton s(t) = t^3 - 8t + 1, where s is measured in feet and t is measured in seconds.(adsbygoogle = window.adsbygoogle || []).push({});

(a) Find the displacement during the first 3 seconds.

(b) Find the average velocity during the first 3 seconds.

(c) Find the instantaneous velocity when t = 3.

(d) Find the acceleration of the particle when t = 3.

(e) At what value or values of t does the particle change direction?

Ok, this is pretty much just to check my answers because i'm paranoid.. Here are the answers i came out with..

(a) 4 ft

(b) 1 ft/s

(c) 19 ft/s

(d) 18 ft/s^2

(e) sqrt(8/3)s or 1.633333s

Is this correct?

Thanks

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# Homework Help: Displacement, velocity, acceleration

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