Each of the following equations has at least one solution

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Each of the following equations has at least one solution EX [#permalink]

08 Oct 2012, 04:19

Each of the following equations has at least one solution EXCEPT

–2^n = (–2)^-n
(2)^-n = (–2)^n
2^n = (–2)^-n
(–2)^n = –2^n
(–2)^-n = –2^-n

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Re: Each of the following equations has at least one solution [#permalink]

08 Oct 2012, 05:00

if -2^n means -(2^n), the answer is A. Otherwise I find 0 to satisfy all equations.
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Re: Each of the following equations has at least one solution [#permalink]

08 Oct 2012, 05:26

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MacFauz wrote:

if -2^n means -(2^n), the answer is A. Otherwise I find 0 to satisfy all equations.

Check these posts:
each-of-the-following-equations-has-at-least-one-solution-94119.html#p724081
each-of-the-following-equations-has-at-least-one-solution-94119.html#p738365
each-of-the-following-equations-has-at-least-one-solution-94119.html#p738571

Hope it helps.
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Re: Exponents [#permalink]

14 Oct 2012, 08:05

Bunuel wrote:

gurpreetsingh wrote:

all seems to have n=0 as solution....? whats the OA

n=0 is not a solution of the equation -2^n = (-2)^{-n} (in fact this equation has no solution):

-2^n=-(2^n)=-(2^{0})=-1 but (-2)^{-n}=(-2)^{0}=1.

Thank you for your response.

I would like to double check why we say that n=0 could be a solution in case of (-2)^{-n}
as (-2)^{-n} = (-2)^{1/n} and then we can not divide by zero?

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Re: Exponents [#permalink]

14 Oct 2012, 23:12

NikRu wrote:

I would like to double check why we say that n=0 could be a solution in case of (-2)^{-n}
as (-2)^{-n} = (-2)^{1/n} and then we can not divide by zero?

Nik

(-2)^{-n} = 1/(-2)^n not (-2)^{1/n}
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Re: Exponents [#permalink]

15 Oct 2012, 11:54

VeritasPrepKarishma wrote:

NikRu wrote:

I would like to double check why we say that n=0 could be a solution in case of (-2)^{-n}
as (-2)^{-n} = (-2)^{1/n} and then we can not divide by zero?

Nik

(-2)^{-n} = 1/(-2)^n not (-2)^{1/n}

Thank you very much!

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Re: Each has one solution except? [#permalink]

17 Jan 2013, 07:27

I lost myself trying to solve this one with algebra; just plug in numbers in similar spots and you'll be fine.
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Each of the following equations has at least one solution [#permalink]

03 Mar 2013, 02:45

Each of the following equations has at least one solution EXCEPT
a. –2^n = (–2)^-n
b. 2^-n = (–2)^n
c. 2^n = (–2)^-n
d. (–2)^n = –2^n
e. (–2)^-n = –2^-n

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Re: Each of the following equations has at least one solution [#permalink]

03 Mar 2013, 03:05

greatps24 wrote:

Merging similar topics. Solutions are on page 1.
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Re: Each of the following equations has at least one solution [#permalink] 03 Mar 2013, 03:05

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Each of the following equations has at least one solution

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