Solve 2^3x=7^(x+1): Logarithms Solution

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To solve the equation 2^{3x} = 7^{x+1}, logarithms are applied, leading to the expression (log2)(3x) = log(7)(x+1). The next step involves simplifying to \frac{3x}{x+1} = \frac{log7}{log2}. However, guidance suggests rearranging the equation to isolate terms involving x on one side. Ultimately, the goal is to solve for x by treating log(2) and log(7) as constants.
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Homework Statement



2^{3x} = 7^{x+1}

Homework Equations



N/A

The Attempt at a Solution



2^{3x} = 7^{x+1}

I'm not entirely sure how to proceed from here. I'm assuming that the following is the right step towards the solution...

(log2)(3x) = log(7)(x+1)

...but I'm not entirely sure.

Any suggestions?

Thanks,
 
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AbsoluteZer0 said:

Homework Statement



2^{3x} = 7^{x+1}

Homework Equations



N/A

The Attempt at a Solution



2^{3x} = 7^{x+1}

I'm not entirely sure how to proceed from here. I'm assuming that the following is the right step towards the solution...

(log2)(3x) = log(7)(x+1)

...but I'm not entirely sure.

Any suggestions?

Thanks,

You are doing just fine. Now solve for x.
 
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I've arrived at

\frac{3x}{x+1} = \frac{log7}{log2}

I'm not sure how to progress.
What should I do next?

Thanks,
 
AbsoluteZer0 said:
I've arrived at

\frac{3x}{x+1} = \frac{log7}{log2}

I'm not sure how to progress.
What should I do next?

Thanks,

You are kind of going the wrong way. You've got log(2)*3x=log(7)(x+1)=log(7)x+log(7). Move all the terms involving x to one side and solve for x. log(2) and log(7) are just numbers.
 
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