If xy = 1
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AleksandrM
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Ian Stewart
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As has been posted elsewhere, there's a typo in the question itself. The solution posted above by netigen, with the x and y terms in the exponents, presented the question in the way it's supposed to be written.
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GMAT dreamer
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We can make things simpler...
If xy=1; it tells that x=1 and y=1, right?
so, 2^(1+1)^2/2^(1-1)^2=
2^2^2/2^0^2=
2^4/2^0=
16/1= 16
Very simple we put numbers.
If xy=1; it tells that x=1 and y=1, right?
so, 2^(1+1)^2/2^(1-1)^2=
2^2^2/2^0^2=
2^4/2^0=
16/1= 16
Very simple we put numbers.
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cramya
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In general if xy=1 does not necessarily mean x=1 and y=1 unless there are other properties about x and y also given that confirms the fact that x=1 y=1If xy=1; it tells that x=1 and y=1, right?
To quote a few:
x=-1 y=-1 xy=1
x=5 y=1/5 xy =1
x=-5 y=-1/5 xy=1
Unless it says x and y are positive integers and xy=1 we cannot assume
x=1 and y=1
Hope this helps!
