1) i'm having trouble with this problem, it looks like their isn't enough information. can someone give me some hints please(adsbygoogle = window.adsbygoogle || []).push({});

http://i2.photobucket.com/albums/y15/seiferseph/untitled.jpg [Broken]

2)

http://i2.photobucket.com/albums/y15/seiferseph/untitled2.jpg [Broken]

i solved parts a-c fine, but i'm having some trouble with d and e

i solved v(t) 6t^2 - 30t + 2 and a(t) = 12t - 30 (taking the derivative). for d and e it is looking for a range, right? heres what i got

d) it is moving left when v(t) < 0, so between the zeros, or 0.676 < t < 4.93

and it is moving right when v(t) > 0, or t < 0.676 and t>2.5

e) p is speeding up when both v(t) and a(t) are in the same direction, and slowing down when they are opposite directions (signs)

i got a(t) > 0 when t > 5/2, and a(t) < 0 when t < 5/2. so its speeding up when t > 4.93 and slowing when 0.676 < t < 2.5

thanks in advance!

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# Homework Help: Derivative problems

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