can someone check my work please thanks, oh btw Im still trying to learn how to use LaTeX mathematical typesetting; I figured itll be slightly faster taking a picture of the problem and my work and posting it here so please bare with me(adsbygoogle = window.adsbygoogle || []).push({});

1. The position of a toy locamotive moving on a straight track along the x-axis is given by the equation x = t^3 - 6t^2 + 9t, where x is in meters and t is in seconds. The net force on the locomotive is equal to 0 when t is equal to (a) zero (b) 2s (c) 3s (d) 4s (e) 5s

(my work)

x = t^3 - 6t^2 + 9t

v = 3t^2 - 12t -- first derivative

a = 6t - 12 -- second derivative

0 = 6t - 12

12 = 6t

t = 2s

Question 2: http://ourworld.cs.com/LezardV4leth/problem_2.jpg [Broken]

Work: http://ourworld.cs.com/LezardV4leth/problem_2_work.jpg [Broken]

Question 3: http://ourworld.cs.com/LezardV4leth/problem_3.jpg [Broken]

Work: http://ourworld.cs.com/LezardV4leth/problem_3_work.jpg [Broken]

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