if xy=1 what is the value of 2^(x+y)^2 / 2^(x-y)^2
ans.16
can someone pls explain
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Simplifying the given expression, we have:yvonne12 wrote:if xy=1 what is the value of 2^(x+y)^2 / 2^(x-y)^2
ans.16
2^(x^2 + 2xy + y^2)/2^(x^2 -2xy + y^2)
2^[(x^2 + 2xy + y^2) - (x^2 -2xy + y^2)]
2^(4xy), since xy = 1, we have 2^4 = 16.
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Here's the full question...
= 2^(4XY) [after we subtract exponents]
= 2^4 [since XY = 1]
= 16
Answer: D
Cheers,
Brent
2^(X+Y)²/ 2^(X-Y)² = 2^(X² + 2XY + Y²)/ 2^(X² - 2XY + Y²)if XY=1 then what is the value of 2^(X+Y)²/ 2^(X-Y)²
A) 2
B) 4
C) 8
D) 16
E) 32
= 2^(4XY) [after we subtract exponents]
= 2^4 [since XY = 1]
= 16
Answer: D
Cheers,
Brent
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Brent@GMATPrepNow wrote:Here's the full question...2^(X+Y)²/ 2^(X-Y)² = 2^(X² + 2XY + Y²)/ 2^(X² - 2XY + Y²)if XY=1 then what is the value of 2^(X+Y)²/ 2^(X-Y)²
A) 2
B) 4
C) 8
D) 16
E) 32
= 2^(4XY) [after we subtract exponents]
= 2^4 [since XY = 1]
= 16
Answer: D
Cheers,
Brent
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Let x=y=1.If XY=1 then what is the value of 2^(X+Y)^2/ 2^(X-Y)2^2
1)2
2) 4
3) 8
4) 16
5) 32
Then:
2^(x+y)² / 2^(x-y)² = 2^(1+1)² / 2^(1-1)² = 2�/2� = 16/1 = 16.
The correct answer is D.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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