2 Part question- Max., & Min. value of function!

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Hello Friends!

Try this question...

The function f(x,y) is such that f(x,y) = x^2.y^3 & x+y =25. Where x, & y are non-negative integers. Select one minimum possible, & one maximum possible value for f(x,y). Make only two selections, one in each column.
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by AbhiJ » Sun Sep 09, 2012 10:49 pm
Min = 0
Max = (5^5)*(2^2)*(3^3) = 337500

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by tanviet » Wed Oct 03, 2012 7:07 pm
how you the the max value? pls, explain.

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by e-GMAT » Sun Dec 09, 2012 11:53 pm
duongthang wrote:how you the the max value? pls, explain.
Hi,

If X+Y=constant; where X & Y are variables,
then (X^m)*(Y^m)=maximum, when X/m=Y/n.

Here, X+Y=25=constant, hence X/2=Y/3 => X = 10, & Y = 15.

=> This gives X^2.Y^3 = 337500.

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by kevincanspain » Tue Dec 11, 2012 2:44 am
Do you think this concept is tested in Integrated Reasoning?
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by tanviet » Thu Feb 07, 2013 11:57 pm
gmat dose not test the formular.