Solve Logarithm Problem: log2 2x -log3 (3x-1) = 2, Find X

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Homework Help Overview

The discussion revolves around solving a logarithmic equation: log2 2x - log3 (3x-1) = 2, with participants seeking guidance on the problem-solving process without receiving direct answers.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss converting logarithmic expressions between different bases and explore the implications of their transformations. There is a focus on verifying the correctness of steps taken and questioning the validity of results obtained.

Discussion Status

Some participants have made progress in transforming the logarithmic expressions and are actively checking their work. There is an acknowledgment of potential errors in calculations, particularly regarding the substitution of values back into the original equation.

Contextual Notes

Participants are navigating the complexities of logarithmic identities and transformations, with some expressing uncertainty about their results and the correctness of their approaches.

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log2 2x -log3 (3x-1) = 2, solve for x...

you guys don't hv 2 solve the question for me, just guide me to the answer:smile:
 
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First step:
Convert one logarithm into its equivalent logarithm expression for the other base.
To do so, the general picture is that for positive number a,b,c, we have:
c=a^{\log_{a}(c)}=b^{\log_{b}(c)}
Taking the a-logarithm of the middle and last expression, we have:
\log_{a}(c)\log_{a}(a)=\log_{b}(c)\log_{a}(b)
That is:
\log_{b}(c)=\frac{\log_{a}(c)}{\log_{a}(b)}
 
ok I've done the 1st step by changing log2 2x to (log3 2x)/(log3 2)

(log3 2x)/(log3 2) - log3 (3x-1) = 2

1.585(log3 2x) -log3 (3x-1) = 2

log3 (2x)^1.585 - log3 (3x-1) = 2

log3 ( (2x^1.585)/(3x-1) ) = 2 , is this correct? then what?
 
ok i went ahead & solve the equation to get x=0.522...but when i substitute x=0.522 into the initial equation i did not get 2...what hv i done wrong?
 

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