Log. functions - comparing solutions, which is best?

In summary, the solutions provided evaluate logarithms and the power of logarithms. One solution is correct while the other is incorrect due to an error in understanding the notation. To avoid confusion, it is recommended to use brackets when applying a function.
  • #1
Tyrannosaurus_
41
2

Homework Statement


I'm not sure what my error is. Both solutions cannot be true.

Homework Equations


evaluating logarithms,
power of logarithms?

The Attempt at a Solution



SOLUTION ONE

=logxxn
=n(logxx)
=n(1)
=nSOLUTION TWO

=logxxn
=(logxx)n
=(1)n
=1

Please help me understand what I've done wrong. Thanks!
 
Last edited:
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  • #2
the logx x^n means logx(x^n) not logx(x)^n so your solution two is wrong.

the logx(x^n) is the same as n * logx(x)
 
  • #3
Tyrannosaurus_ said:
SOLUTION TWO

=logxxn
=(logxx)n
=(1)n
=1

Please help me understand what I've done wrong. Thanks!
Let ##y = \log_x x^n##. Then ##x^y = x^n \Rightarrow y = n##, so your solution one is correct.
##x^n## is in the argument of the log, the log is not to the nth power.
 
  • #4
The other 2 posts are correct:

Your solution 1 uses logx(xn)
Your solution 2 uses (logx(x))n

An easy way to avoid this is to use brackets whenever applying a function:
 

1. How do log functions work?

Logarithmic functions are the inverse of exponential functions. They represent the power to which a base number must be raised to equal a given number. For example, log base 2 of 8 is equal to 3, because 2 to the power of 3 equals 8.

2. What is the purpose of comparing solutions using log functions?

Comparing solutions using log functions can help us determine which solution is the most efficient or optimal. It allows us to compare numbers on a more manageable scale, and can also reveal patterns and relationships between data points.

3. How do you determine which solution is the best using log functions?

The best solution is typically the one with the lowest log value. This means that it requires the least amount of effort or resources to achieve the desired result. However, it is important to also consider other factors such as practicality and cost when determining the best solution.

4. Can log functions be used for any type of problem?

Log functions are most commonly used for problems involving exponential growth or decay, but they can also be applied to other types of problems such as finance, physics, and biology. They are a powerful tool for analyzing data and making predictions.

5. Are there any limitations to using log functions to compare solutions?

One limitation of using log functions to compare solutions is that they can only be applied to numerical data. They also assume a linear relationship between the data points, which may not always be the case. Additionally, log functions may not be the best tool for comparing solutions in every situation, so it is important to consider other methods as well.

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