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Help plez? couple of issues (1 Viewer)

hayabusaboston

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So ive been having memory lapses of 3u material recently, am somewhat irritated at myself for not remembering how to do certain things. Could you guys help me out perhaps? Im also superbly uncertain of a whole bunch of things.
1. A particles velocity is gien by equation v^2=252+216x-36x^2
c) If particle is initially at one of its endpoints, find its displacement when t=13pi/12 seconds. Is the answer 4?
d)Find the average speed of the particle in the first 13pi/12 seconds (6pi/12?)

3.Show that x=3 is an approximation to the root of the equation x=6-3lnx. (Was totally wtf, apparently showing there's a change in sign from halving the interval with 2.5 and 3.5 was wrong, as was subbing in 3 into LHS and RHS... how do u "show" it?)
 
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braintic

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2. Pretty certain this is beyond the course. I'll need more time to think it through. But a quick substitution of x=1 showed your answer to be incorrect.
 

Shadowless

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I meant for Q1, seeing as there are only parts c and d up there.
 

Joelolol

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Q3) dont uu just use newtons method of approximation? x=a-[f(a)/F'(a)] im not too sure.. :S
 

Joelolol

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Q4) i cant be too sure, but try subbing in the coordinates of (5,4) into the equation of the tangent, then find the values of m and substitute the m back into the equation of tangent! :D
 

hayabusaboston

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Q3) dont uu just use newtons method of approximation? x=a-[f(a)/F'(a)] im not too sure.. :S
Nup, I did that, and teachers like "You didnt SHOW me WHY"

And in my head im like "well FUCK you HOW ELSE" lol.

But no, my teachers a super good teacher, really nice.
 

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