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November 13th, 2007, 11:33 PM
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| |  Could be easy, but I am stumped.
If ![f(x)=3x^2-\frac{8}{x '}\](http://www.mathhelpforum.com/math-help/latex2/img/1ec16d41a1acd7c36cbcb02be11d1294-1.gif "f(x)=3x^2-\frac{8}{x '}\") , find the positive value of  for which  is least.
I don't think I have ever seen a function with x' mixed up in there and I can't seem to even get started. Thanks in advance for any help. |
November 14th, 2007, 02:25 AM
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Quote:
Originally Posted by jabroni1212  If , find the positive value of for which is least.
I don't think I have ever seen a function with x' mixed up in there and I can't seem to even get started. Thanks in advance for any help. | Are you sure that the prime on the x is not just a comma (not part of the formula at all)? |
November 14th, 2007, 09:20 AM
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I just tried it without the x' just as x, and I got the right anwer. Thanks. Wierd it really looks like an x'.
Last edited by jabroni1212; November 14th, 2007 at 09:34 AM.
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November 14th, 2007, 09:27 AM
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Quote:
Originally Posted by jabroni1212 I just tried it without the x' just as x, and it doesn't seem to minimize. I am pretty sure it is as I wrote above. |  has a (relative) minimum. You just have to work at it a bit.
Otherwise, I'd just treat the x' as a constant.
-Dan
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November 14th, 2007, 11:53 AM
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Thats a disappointing answer, I had several theories, but was keeping my mouth shut until someone more educated than me found the correct answer. :P
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