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If 3^(-x) + 3^(-x) + 3^(-x) = 1, what is the value of x?
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05 Nov 2017, 23:25
05 Nov 2017, 23:25
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Question Stats:
80% (00:45) correct
19% (03:12) wrong based on 42 sessions
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If \(3^{-x}+3^{-x}+3^{-x}=1\), what is the value of x?
A. -1
B. -1/2
C. 1/3
D. 1/2
E. 1
Kudos for correct solution.
A. -1
B. -1/2
C. 1/3
D. 1/2
E. 1
Kudos for correct solution.
Re: If 3^(-x) + 3^(-x) + 3^(-x) = 1, what is the value of x?
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06 Nov 2017, 05:57
06 Nov 2017, 05:57
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The expression above can be rewritten as \(3*3^{-x}=1\).
Then, each number to the power of zero is equal to 1, thus we can rewrite 1 as 3^0 and we get \(3^{1-x}=3^0\).
Finally, in order to have the two sides of the equation equal, it must be that the exponents are equal, i.e. \(1-x=0\). From which we get x = 1.
Answer E
Then, each number to the power of zero is equal to 1, thus we can rewrite 1 as 3^0 and we get \(3^{1-x}=3^0\).
Finally, in order to have the two sides of the equation equal, it must be that the exponents are equal, i.e. \(1-x=0\). From which we get x = 1.
Answer E
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Re: If 3^(-x) + 3^(-x) + 3^(-x) = 1, what is the value of x?
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09 Dec 2023, 03:07
09 Dec 2023, 03:07
\(3^{-x}+3^{-x}+3^{-x}=1\)
=> 3 * \(3^{-x}\) = 1
=> \(3^1 * 3^{-x}\) = \(3^0\)
=> \(3^{1 - x}\) = \(3^0\)
Since base is same (3) so powers will also be same
=> 1 - x = 0
=> x = 1
So, Answer will be E
Hope it helps!
Watch the following video to learn the Basics of Exponents
=> 3 * \(3^{-x}\) = 1
=> \(3^1 * 3^{-x}\) = \(3^0\)
=> \(3^{1 - x}\) = \(3^0\)
Since base is same (3) so powers will also be same
=> 1 - x = 0
=> x = 1
So, Answer will be E
Hope it helps!
Watch the following video to learn the Basics of Exponents
