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5va
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Bunuel
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5va
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I had this problem today, but it's actually this:

2^[(x+y)^2] / 2^[(x-y)^2]

It won't show up correctly using LATEX.

You simplify it to 2^[(x+y)^2 - (x-y)^2], and:

\((x+y)^2 - (x-y)^2 = x^2 + 2xy + y^2 - (x^2 - 2xy + y^2)\)
\(= 2xy + 2xy = 4xy\)

And, since xy = 1, you're left with 2^4 = 16.
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TehJay
I had this problem today, but it's actually this:

It won't show up correctly using LATEX.

You simplify it to 2^[(x+y)^2 - (x-y)^2], and:

\((x+y)^2 - (x-y)^2 = x^2 + 2xy + y^2 - (x^2 - 2xy + y^2)\)
\(= 2xy + 2xy = 4xy\)

And, since xy = 1, you're left with 2^4 = 16.

Assuming the question is as you mentioned:

\(\frac{2^{(x+y)^2}}{2^{(x-y)^2}}\)

Given that xy = 1, if you are asked a unique value of the given expression, it means it will have the same value for all x and y under the constraint xy = 1. So just put x = 1, y = 1, you get

\(\frac{2^{(1+1)^2}}{2^{(1-1)^2}}\)

\(2^4\)

16
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VeritasKarishma
TehJay
I had this problem today, but it's actually this:

It won't show up correctly using LATEX.

You simplify it to 2^[(x+y)^2 - (x-y)^2], and:

\((x+y)^2 - (x-y)^2 = x^2 + 2xy + y^2 - (x^2 - 2xy + y^2)\)
\(= 2xy + 2xy = 4xy\)

And, since xy = 1, you're left with 2^4 = 16.

Assuming the question is as you mentioned:

\(\frac{2^{(x+y)^2}}{2^{(x-y)^2}}\)

Given that xy = 1, if you are asked a unique value of the given expression, it means it will have the same value for all x and y under the constraint xy = 1. So just put x = 1, y = 1, you get

\(\frac{2^{(1+1)^2}}{2^{(1-1)^2}}\)

\(2^4\)

16


VeritasKarishma , so in official GMATprep question we are dealing with exponents you mean ? :?
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5va just wasted 20 minutes, trying to solve the issue. Can you please edit the question for other people?
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5va
If xy=1, what is the value of 2(x+y)^2/2(x-y)^2?

A. 2
B. 4
C. 8
D. 16
E. 32

PROPER VERSION OF THIS QUESTION IS HERE: if-xy-1-what-is-the-value-of-2-x-y-2-2-x-y-107238.html

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