Guest Posted March 18, 2010 Report Share Posted March 18, 2010 (edited) Determine all possible pair(s) (x, y) of nonzero real numbers that satisfy this system of equations: (3*x)log 3 = (7*y)log 7, and: 7log x = 3log y Note: All logarithms are considered in base ten. Edited March 18, 2010 by K Sengupta Quote Link to comment Share on other sites More sharing options...
0 Guest Posted March 19, 2010 Report Share Posted March 19, 2010 I see only one solution x=1/3 and y=1/7. Taking the log of the first equation. and the log of the second equation, we can eliminate log x and end up with log 7 + log y = 0 Quote Link to comment Share on other sites More sharing options...
0 Guest Posted March 19, 2010 Report Share Posted March 19, 2010 I found that if y = 3, x is approximately 16.33; Quote Link to comment Share on other sites More sharing options...
0 Guest Posted March 21, 2010 Report Share Posted March 21, 2010 (edited) Taking the second equation we found that logx=logy*log3/log7 From the first equtation log3(log3+logx)=log7(log7+logy) replacing logx=logy*log3/log7 We find that y=1/7 and x=1/3 Edited March 21, 2010 by Glosom Quote Link to comment Share on other sites More sharing options...
0 dark_magician_92 Posted January 11, 2011 Report Share Posted January 11, 2011 Determine all possible pair(s) (x, y) of nonzero real numbers that satisfy this system of equations: (3*x)log 3 = (7*y)log 7, and: 7log x = 3log y Note: All logarithms are considered in base ten. by eliminating log x or log y, we can solve the 2 eqns to find x=1/3, y=1/7 Quote Link to comment Share on other sites More sharing options...
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Guest
Determine all possible pair(s) (x, y) of nonzero real numbers that satisfy this system of equations:
(3*x)log 3 = (7*y)log 7, and:
7log x = 3log y
Note: All logarithms are considered in base ten.
Edited by K SenguptaLink to comment
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