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# n is an integer.

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n is an integer. [#permalink]  11 Dec 2017, 02:48
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100% (00:26) correct 0% (00:00) wrong based on 8 sessions
n is an integer.

 Quantity A Quantity B $$(-1)^n(-1)^{n+2}$$ $$1$$

A. Quantity A is greater.
B. Quantity B is greater.
C. The two quantities are equal
D. The relationship cannot be determined from the information given.
[Reveal] Spoiler: OA

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Re: n is an integer. [#permalink]  11 Dec 2017, 02:58
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Hello,

Since (-1)^n is multiplied with (-1)^n+1 and has the same basis we can add both
-1^n+n+2 which is -1^2n+2

We know that any even or odd numbers (n could be 2,4,6 or 3,5,7), it will always lead to an even answer. The result is therefore always even. The +2 added afterwards will keep the answer even.
We know that a negative number with an exponent will always lead to a positive answer so -1 becomes 1.
The result is C.

Any one can confirm this?
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Joined: 18 Apr 2015
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Kudos [?]: 980 [1] , given: 4506

Re: n is an integer. [#permalink]  14 Dec 2017, 13:55
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Regards
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Re: n is an integer.   [#permalink] 14 Dec 2017, 13:55
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