I just took an official CAT with a pretty good outcome... but I don't know why I got the FIRST freakin question wrong.... i did 75 times and still can't get to the right answer...
(2^(41)^2)/(2^(32)
OA: [spoiler]2^8[/spoiler]
help...
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 Rahul@gurome
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(2^(41)^2)/(2^(32) = (2^3^2)/(2^1) = (2^9)/2 = 2^(91) = 2^8shibal wrote:I just took an official CAT with a pretty good outcome... but I don't know why I got the FIRST freakin question wrong.... i did 75 times and still can't get to the right answer...
(2^(41)^2)/(2^(32)
OA: [spoiler]2^8[/spoiler]
Rahul Lakhani
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but by exponent rules (2^3)^2 be 2^(3*2)???Rahul@gurome wrote:(2^(41)^2)/(2^(32) = (2^3^2)/(2^1) = (2^9)/2 = 2^(91) = 2^8shibal wrote:I just took an official CAT with a pretty good outcome... but I don't know why I got the FIRST freakin question wrong.... i did 75 times and still can't get to the right answer...
(2^(41)^2)/(2^(32)
OA: [spoiler]2^8[/spoiler]
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 Rahul@gurome
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The question is (2^(41)^2)/(2^(32)shibal wrote:
but by exponent rules (2^3)^2 be 2^(3*2)???
Numerator = (2^(41)^2) = 2^3^2
3^2 = 9, so numerator reduces to 2^9
Now denominator = 2^(32) = 2^1 = 2
Therefore, 2^9/2 = 2^(91) = 2^8
We cannot write (2^3)^2 = 2^(3*2), as 2^3^2 = 2^(3^2) = 2^9
2^3^2 means 2 is a power of 3, which is again a power of 2, so first solve 3^2 = 9 and then the expression reduces to 2^9.
Does that help?
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Rahul@gurome wrote:The question is (2^(41)^2)/(2^(32)shibal wrote:
but by exponent rules (2^3)^2 be 2^(3*2)???
Numerator = (2^(41)^2) = 2^3^2
3^2 = 9, so numerator reduces to 2^9
Now denominator = 2^(32) = 2^1 = 2
Therefore, 2^9/2 = 2^(91) = 2^8
We cannot write (2^3)^2 = 2^(3*2), as 2^3^2 = 2^(3^2) = 2^9
2^3^2 means 2 is a power of 3, which is again a power of 2, so first solve 3^2 = 9 and then the expression reduces to 2^9.
Does that help?
hummm so can I conclude that (2^3)^2 is different from (2^3^2)?
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 Rahul@gurome
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Yes definitely, they are different.shibal wrote:
hummm so can I conclude that (2^3)^2 is different from (2^3^2)?
2^3 = 8 so (2^3)^2 = 8^2 = 64
and 2^3^2 = 2^(3^2) = 2^9
Rahul Lakhani
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