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National and Regional Contests
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MAA AMC
AMC 12/AHSME
1991 AMC 12/AHSME
3
Exponents
Exponents
Source: AHSME 1991 problem 3
October 15, 2011
AMC
Problem Statement
(
4
−
1
−
3
−
1
)
−
1
=
(4^{-1} - 3^{-1})^{-1} =
(
4
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1
−
3
−
1
)
−
1
=
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A
)
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12
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C
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12
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D
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12
<span class='latex-bold'>(A)</span>\ -12\qquad<span class='latex-bold'>(B)</span>\ -1\qquad<span class='latex-bold'>(C)</span>\ \frac{1}{12}\qquad<span class='latex-bold'>(D)</span>\ 1\qquad<span class='latex-bold'>(E)</span>\ 12
<
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1
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E
)
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12
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