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A couple of Logs (Posted on 2002-06-04) Difficulty: 4 of 5
logy(x) + logx(y) = 43

What are the values of x and y?

  Submitted by Dulanjana    
Rating: 2.4375 (16 votes)
Solution: (Hide)
Consider the definition of a log, and you will see that loga(b) = 1/(logb(a)).

Let's say that logy(x) equals some number A. Then A + 1/A = 43. This can be written in the form: A^2 + 1 = 43A.

Solving this quadratic equation yields A = 43.977 or A = 0.023. (These two values are reciprocal of one another, so they are identical for our purposes)

Now to solve the problem, take any number (such as 2) and raise it to the power of 42.977. As you can see, there is an infinite number of solutions, but none of them are particularly elegant.

Comments: ( You must be logged in to post comments.)
  Subject Author Date
A hint...danish ahmed khan2012-10-23 14:28:55
Some Thoughtssome thoughtsK Sengupta2007-11-23 05:11:10
SolutionSolution To The ProblemK Sengupta2007-03-19 11:47:41
No SubjectJack Squat2003-12-31 17:51:30
re: re(23424): Strange (Still no integer/special solution)friedlinguini2002-06-05 06:42:28
re(23424): Strange (Still no integer/special solution)levik2002-06-05 06:28:53
re: re: re: re(2): Strange (Still no integer/special solution)Dulanjana2002-06-05 03:43:02
re: re: re(2): Strange (Still no integer/special solution)Ender2002-06-05 03:15:06
re: re: re(2): Strange ( A bit more to it)Dulanjana2002-06-05 00:39:08
re: re(2): StrangeDulanjana2002-06-04 15:29:27
re: Just Jokinglevik2002-06-04 12:00:22
Just JokingTomM2002-06-04 11:16:55
re(2): Strangelevik2002-06-04 09:25:24
Possible solution?Ender2002-06-04 07:01:02
No unique solutionfriedlinguini2002-06-04 06:57:17
re: StrangeDulanjana2002-06-04 06:45:39
Strangelevik2002-06-04 05:30:02
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