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Trev

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AreYouAlright? said:
I love Terry Lee so F$#%ing much right now, i did this by setting the discriminant equal to zero i didn't know what elso to do.. gave me 4 sqrt 3 which is this answer. Yes, i rule! Of course so does Terry Lee!
That's what I did, but is that just a coincidence it's the same answer or is it actually right? (please be, I need those 2 marks :()
 

justchillin

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It doesnt matter man...1 mark is for working, one is for the answer...be happy u got it :D
 

AreYouAlright?

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It is actually quite mathematically correct. Finding the discriminant and setting it equal to zero would mean that, that quadric equation would have ONE real root. Which would mean on either side of E the chord would be of equal lenth. This would constitute the shortest chord. Therefore this gives us an expression in lenghth squared which we don't need to sub back in as we have it in terms of length.

By differentiating and finding x when the differential is equal to zero you would then have to sub this back into the line multiplied by two to get the same answer. Our way we are not finding an X-value, we are stating the x-value is the same for either side and finding the length straight off.

A much more elegant solution if you ask me :D
 

Estel

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l = x + 12/x = (rtx-rt(12/x))^2 + 2rt 12 >= 2rt 12
'nuff said about elegance :p.
 

AreYouAlright?

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Estel said:
l = x + 12/x = (rtx-rt(12/x))^2 + 2rt 12 >= 2rt 12
'nuff said about elegance :p.
I really should be careful when i start throwing that word around... :eek:
 

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