2^(4-1)^2 / 2^(3-2)

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2^(4-1)^2 / 2^(3-2)

by massi2884 » Sat Mar 24, 2012 8:30 am
2^(4-1)^2 / 2^(3-2)

2^8
2^7
2^6
2^5
2^4

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by seal4913 » Sat Mar 24, 2012 9:55 am
So first look at (4-1) that is 3 so then you get 3 squared is 9 so it's 2^9 divided by 2^1

So when you have the same base and it's division you can subtract the exponents. So 9 - 1 = 8.

Therefore the answer is [spoiler]A 2^8[/spoiler]

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by gmatmath » Fri Apr 06, 2012 8:41 am
This problem can have 2 solutions depending on how the parenthesis are placed.

case1: [2^(4-1)]^2 / 2^(3-2)
= (2^3)^2 / 2
= 2^6/2
= 2^5

case2: 2^[(4-1)^2]/2^(3-2)
= 2^[3^2]/2
= 2^9/2
=2^8

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by Bill@VeritasPrep » Fri Apr 06, 2012 8:56 am
gmatmath wrote:This problem can have 2 solutions depending on how the parenthesis are placed.

case1: [2^(4-1)]^2 / 2^(3-2)
= (2^3)^2 / 2
= 2^6/2
= 2^5

case2: 2^[(4-1)^2]/2^(3-2)
= 2^[3^2]/2
= 2^9/2
=2^8
It should be the second way. See https://www.beatthegmat.com/2-4-1-2-t41974.html
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