First off i'd like to say Hi to the forums, hehe. I didn't really see a new member area but I suppose this will do. Right now I'm kind of struggling with these two problems that I recently took a quiz on and didn't do so well. I've been trying to figure out how to work them out but i just dont really get it. if anyone could help out it'd be awesome.(adsbygoogle = window.adsbygoogle || []).push({});

(1)

The position (in cm) of a particle along the x-axis at time t(in s) is given by X(t) = t^3-6t^2+8t, t is greater than or equal to 0.

the question:

When is the particle moving to the left? the right?

Acceleration of the particle when the speed is zero.

Total distance traveled from t=0 to t=2.

(2)

( and the one that REALLY gets me)

A person standing 30ft from the base of a building measures the angle of elevation to the top of the building as being 75 degrees with an error of +or- 1.2 degrees.

What is the max error in estimating the height of the building, and the percentage error?

This one has taken me quite a while, I am thinking it has something to do with the law of sines, but when i try it with that method i'm getting a completely unreasonable answer. I kind of have the right idea, i hope, but for some reason i'm just not seeing it.

Thank you in advance for those who wish to take on these.

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# A Rate of change and a differentials problem

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