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enthada | 13:42 Tue 30th May 2006 | Quizzes & Puzzles
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Find the least value of 3x + 4y if x2y3 = 6.
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Minimum value is 10, when x = 4/3 and y = 3/2.
14:16 Tue 30th May 2006
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Method:Substituting for y then Q =3x + 4(6x^(-2))^(1/3)


Hence dQ/dx = 3 - 8[6x^(-5)]^(1/3) /3


Now dQ/dx = 0 if x^5 = 2^10/3^5 that is x = 4/3


The rest follows.

14:36 Tue 30th May 2006
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Thats what i was going to say :)
14:54 Tue 30th May 2006
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Mickey_Blue The "J" question was just a diversion to distract you away from this posting, so that I could get a "free pot" at it! I knew that you were "on line" and "hungery" for questions!
15:08 Tue 30th May 2006

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