How do I Solve a Basic Logarithm Problem?

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Discussion Overview

The discussion revolves around solving logarithm problems, specifically focusing on finding the variable x in different logarithmic equations. Participants explore various forms and interpretations of logarithmic expressions.

Discussion Character

  • Homework-related
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant presents a logarithmic equation: \(^{3x-2}\log 100 = ^2\log 4\) and attempts to solve it, leading to \(x = 4\).
  • Another participant questions the interpretation of the logarithmic notation, suggesting it might be \(\log_{100}(3x - 2) = \log_4 (2)\).
  • A different logarithmic equation is introduced: \(\log_{2x-5}125 = \log_28\), with a subsequent solution leading to \(x = 5\).
  • Some participants express confusion over the notation used in the logarithmic expressions, indicating a lack of familiarity with the format.

Areas of Agreement / Disagreement

Participants express differing interpretations of the logarithmic notation and the equations presented. There is no consensus on the correct form or solution for the logarithmic problems discussed.

Contextual Notes

Participants have not clarified certain assumptions regarding the notation of logarithms, and there are unresolved questions about the correct interpretation of the equations.

susanto3311
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hi guys..

i need help to solve logarithm problem

how to find x?

thanks any help..
 

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susanto said:
\text{Solve for }x:\;^{3x-2}\log 100 \:=\:^2\log 4.
I've never seen logarithms written like that . . .

\begin{array}{ccc}\text{We have:} &amp; \log_{3x-2}100 \:=\:\log_24 \\<br /> &amp; \log_{3x-2}100 \:=\:2 \\<br /> &amp; (3x-2)^2 \:=\:100 \\<br /> &amp; 3x-2 \:=\:10 \\<br /> &amp; 3x\:=\:12 \\<br /> &amp; x \:=\:4<br /> \end{array}

 
susanto3311 said:
hi guys..

i need help to solve logarithm problem

how to find x?

thanks any help..
Is this supposed to be [math]\text{log}_{100}(3x - 2) = \text{log}_4 (2)[/math]?

-Dan
 
hi...

what is finally for x?
 
hi soroban...
thank, but how about this...

\begin{array}{ccc}\text{We have:} &amp; \log_{2x-5}125 \:=\:\log_28 \\<br /> <br /> - - - Updated - - -<br /> <br /> <blockquote data-attributes="member: 703424" data-quote="soroban" data-source="post: 6750174" class="bbCodeBlock bbCodeBlock--expandable bbCodeBlock--quote js-expandWatch"> <div class="bbCodeBlock-title"> soroban said: </div> <div class="bbCodeBlock-content"> <div class="bbCodeBlock-expandContent js-expandContent "> I&#039;ve never seen logarithms written like that . . .<br /> <br /> \begin{array}{ccc}\text{We have:} &amp;amp; \log_{3x-2}100 \:=\:\log_24 \\&lt;br /&gt; &amp;amp; \log_{3x-2}100 \:=\:2 \\&lt;br /&gt; &amp;amp; (3x-2)^2 \:=\:100 \\&lt;br /&gt; &amp;amp; 3x-2 \:=\:10 \\&lt;br /&gt; &amp;amp; 3x\:=\:12 \\&lt;br /&gt; &amp;amp; x \:=\:4&lt;br /&gt; \end{array} </div> </div> </blockquote><br /> hi soroban...
 

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susanto3311 said:
\log_{2x-5}125 \:=\:\log_28
\begin{array}{cc}\log_{2x-5}125 \:=\: \log_28 \\<br /> \log_{2x-5}125 \:=\:3 \\<br /> (2x-5)^3 \:=\:125 \\<br /> 2x-5 \:=\: 5 \\<br /> 2x \:=\: 10 \\<br /> x \:=\:5<br /> \end{array}
- - Updated - - -
 

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