Exponents

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by vishubn » Sat Nov 22, 2008 10:18 am
ya my takes is A

2^16-1 is the ans ! please confirm !!

its of the form
(a+b)(a-b)=a^2-b^2

so every term taken in this way leads to 2^16-1

if its the right OA please confirm ! as well post the entire explanantion :)

Vishu
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by earth@work » Sat Nov 22, 2008 12:11 pm
i m also getting A : 2^16-1
my method too same as vishu
(2^2-1)(2^2+1)(2^4+1)(2^8+1) = )(2^4-1)(2^4+1)(2^8+1)
=(2^8-1)(2^8+1)=2^16-1

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It is A

by Ossa » Sat Nov 22, 2008 4:44 pm
Hi,

Yes, the answer is A, and I think yours is the best way to do it.

earth@work wrote:i m also getting A : 2^16-1
my method too same as vishu
(2^2-1)(2^2+1)(2^4+1)(2^8+1) = )(2^4-1)(2^4+1)(2^8+1)
=(2^8-1)(2^8+1)=2^16-1
Ossa Elhadary, PhD, CISA, PMP
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