How can I simplify this logarithmic equation on a TI89 titanium?

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SUMMARY

The discussion focuses on simplifying logarithmic equations using the TI-89 Titanium calculator. Users commonly approach base changes of logarithms differently, but a straightforward method involves using the command "Diamond" followed by 7 to access the log() function. The equation 5lnx + 6lny - 4lnz simplifies to ln(x^5*y^6/z^4). To maintain accuracy, it is recommended to use ln(e^(5 ln x + 6 ln y - 4 ln z)), utilizing the diamond-x function for e.

PREREQUISITES
  • Understanding of logarithmic properties, specifically the laws of logarithms.
  • Familiarity with the TI-89 Titanium calculator functionalities.
  • Basic algebra skills, particularly with exponential and logarithmic equations.
  • Knowledge of the natural logarithm (ln) and its applications.
NEXT STEPS
  • Research the properties of logarithms and their applications in algebra.
  • Explore advanced functions of the TI-89 Titanium, including the use of the "Diamond" key.
  • Learn how to manipulate logarithmic expressions for simplification.
  • Investigate the implications of using complex numbers in logarithmic equations.
USEFUL FOR

Students, educators, and anyone using the TI-89 Titanium for mathematical computations, particularly those dealing with logarithmic equations and simplifications.

calypsob
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First of all I would like to share this because I randomly found it and I commonly see that people approach base changes of common logs on the ti89 titanium in a very different way.
Scroll half way down page 2 http://education.ti.com/xchange/AUS-NZ/Mathematics/Number/12250/SomehelpQAontheTI89.pdf
Also, the command "Diamond" and then 7 opens the log() function on ti89 titanium

Ok on to my question.

is there a quick way to enter this equation and simplify?

5lnx+6lny-4lnz =

The answer is ln(x^5*y^6/z^4)
 
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You lose some accuracy if you use complex numbers, but one easy way is to do ln(e^(5 ln x + 6 ln y - 4 ln z)). Use diamond-x for e^, or CHAR-MATH-5 also gives you the correct e.

This is just a simple algebra trick: ln(e^x)) = x, but the calculator doesn't try to simplify anymore. If you do e^ln(x), your domain is limited to positive numbers, and the calculator changes the format again.
 

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