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p_gorsky
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Book 6-Chapter 3-bottom of pg. 41

by p_gorsky Wed Sep 11, 2013 6:55 pm

Hi, I don't understand how we simplify Quant A and Quant B down to (2v-1)&=2(2v-1)-1. I get the first side, but not the second. Please explain!

Thanks!
vimal.kapur
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Re: Book 6-Chapter 3-bottom of pg. 41

by vimal.kapur Thu Sep 12, 2013 2:26 pm

p_gorsky Wrote:Hi, I don't understand how we simplify Quant A and Quant B down to (2v-1)&=2(2v-1)-1. I get the first side, but not the second. Please explain!

Thanks!


v=(2v-1)/&;substitute this value on LHS.
{2(2v-1)/&-1}&=2(2v-1)-&=4v-2-&

Even with above,A is always less than B

Vimal Kapur
p_gorsky
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Re: Book 6-Chapter 3-bottom of pg. 41

by p_gorsky Thu Sep 12, 2013 7:24 pm

I still need more explanation of how we simplify to get 2(2v-1)-1.

Thanks!
tommywallach
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Re: Book 6-Chapter 3-bottom of pg. 41

by tommywallach Mon Sep 16, 2013 7:03 pm

Hey Pgorsky,

You do understand that this is a function question, right? Not straight algebra. It might help to see it this way:

f(x) = 2x - 1

Column A: f(f(x))
Column B: 4x

Does that make it easier? It's the same thing; they're just using a silly made-up symbol instead of f(x), which the GRE enjoys doing.

-t
p_gorsky
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Re: Book 6-Chapter 3-bottom of pg. 41

by p_gorsky Tue Sep 17, 2013 4:07 pm

OHHHHHH!!! Thanks so much! Got it :)
tommywallach
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Re: Book 6-Chapter 3-bottom of pg. 41

by tommywallach Wed Sep 25, 2013 2:57 pm

Glad to help! : )

-t