Difference between revisions of "2013 AIME I Problems/Problem 8"

(Created page with "== Problem 8 == The domain of the function f(x) = arcsin(log<math>_{m}</math>(''nx'')) is a closed interval of length <math>\frac{1}{2013}</math> , where ''m'' and ''n'' are posi...")
 
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== Solution ==
 
== Solution ==
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The domain of the arcsin function is [-1, 1], so -1 <math>\le</math> log<math>_{m}</math>(''nx'') <math>\le</math> 1.
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<math>\frac{1}{m} \le nx \le m</math>
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<math>\frac{1}{mn} \le x \le \frac{m}{n}</math>
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<math>\frac{1}{mn} - \frac{m}{n} = \frac{1}{2013}</math>

Revision as of 20:01, 15 March 2013

Problem 8

The domain of the function f(x) = arcsin(log$_{m}$(nx)) is a closed interval of length $\frac{1}{2013}$ , where m and n are positive integers and m > 1. Find the remainder when the smallest possible sum m + n is divided by 1000.


Solution

The domain of the arcsin function is [-1, 1], so -1 $\le$ log$_{m}$(nx) $\le$ 1.

$\frac{1}{m} \le nx \le m$

$\frac{1}{mn} \le x \le \frac{m}{n}$

$\frac{1}{mn} - \frac{m}{n} = \frac{1}{2013}$