Solve Logarithmic Equation: [log_{2} 9/log_{2} 10] - log 3

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The discussion centers on simplifying the expression [log_{2} 9/log_{2} 10] - log 3 into a single logarithm. The solution reveals that log_{2} 9/log_{2} 10 can be converted to log_{10} 9, leading to the simplification log 9 - log 3, which equals log (9/3) or log 3. Participants clarify the distinction between an equation and an expression, emphasizing the limitations on operations applicable to expressions. The original poster expresses gratitude for the assistance received. Understanding logarithmic properties and the correct terminology is crucial for solving such problems effectively.
nvez
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Homework Statement


I have to take the following equation and make it one single log

[log_{2} 9/log_{2} 10] - log 3

The answer is equal to: log 3

I usually know how to do this however I have no clue in this case, I have the answer however.

Homework Equations



None?
log x - log y = log (x/y)
log x + log y = log (x*y)

The Attempt at a Solution


I have tried the putting what the divison part really is equal too then subtracting it or whatever but to no avail.

I appreciate help in advanced.
 
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Try changing the base to log10 (I assumed that is what log was)
 
Thank you very much!

For future reference:

logc m = logs m / logs c

In this case:

log2 9 / log2 10 = log10 9

log 9 - log 3 = log (9/3) = log 3

Thanks again.
 
nvez said:

Homework Statement


I have to take the following equation and make it one single log

[log_{2} 9/log_{2} 10] - log 3
A small point: this is not an equation. It's important to understand when you're working with an equation and when you're working with an expression, since the kinds of operations you can do are different. For example, if you're working with an equation, you can add a quantity to both sides, multiply both sides by a quantity, and so on, but you're very limited in the things you can do with just an expression.
 
Mark44 said:
A small point: this is not an equation. It's important to understand when you're working with an equation and when you're working with an expression, since the kinds of operations you can do are different. For example, if you're working with an equation, you can add a quantity to both sides, multiply both sides by a quantity, and so on, but you're very limited in the things you can do with just an expression.

Ahh, I see!

Thank you very much again! :)
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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