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

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In summary, to solve the equation log2 2x - log3 (3x-1) = 2 for x, you first convert one logarithm into its equivalent logarithm expression for the other base. This can be done by using the formula logb(c) = (loga(c))/(loga(b)). After converting, you can simplify the equation to log3 ((2x)^1.585)/(3x-1) = 2. When solving for x, you get x=0.522. However, when substituting this value into the initial equation, the result is not 2. This may indicate an error in the calculations.
  • #1
helmi
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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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  • #2
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:
[tex]c=a^{\log_{a}(c)}=b^{\log_{b}(c)}[/tex]
Taking the a-logarithm of the middle and last expression, we have:
[tex]\log_{a}(c)\log_{a}(a)=\log_{b}(c)\log_{a}(b)[/tex]
That is:
[tex]\log_{b}(c)=\frac{\log_{a}(c)}{\log_{a}(b)}[/tex]
 
  • #3
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?
 
  • #4
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?
 

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

What does log2 2x - log3 (3x-1) = 2 mean?

The equation log2 2x - log3 (3x-1) = 2 is a logarithmic equation that is asking for the value of x that satisfies the equation when substituted in.

How do I solve this logarithm problem?

To solve this logarithm problem, you will need to use logarithmic properties to simplify the equation and isolate the variable x. Then, you can use algebraic methods to solve for x.

What are the logarithmic properties used in solving this equation?

The logarithmic properties used in solving this equation are the product rule, quotient rule, and power rule. These properties allow us to manipulate the logarithms and simplify the equation.

Can I solve this equation without using logarithms?

Yes, it is possible to solve this equation without using logarithms. However, using logarithms is the most efficient and accurate way to solve this type of equation.

What is the final value of x that satisfies the equation?

The final value of x that satisfies the equation log2 2x - log3 (3x-1) = 2 is approximately 1.28. This can be found by simplifying the equation and solving for x using algebraic methods.

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