Understanding Logarithmic Properties: Explained with Examples

In summary, the conversation discusses the logarithmic property where (log base c of a)^b is equal to b (log base c of a). The individual is struggling to understand this property when inputting specific numbers and mentions a discrepancy, but it is clarified that the correct formula is log_c(a^b) = b log_c (a). This is proven by taking the base c exponential of each side.
  • #1
Rafe
2
0
Okay i did a search for logarithmic properties and logarithms and couldn't seem to find an explanation for how this particular property works.
(log base c of a ) ^ b = b (log base c of a)
when i input simple numbers like :
PHP:
a=4
b=3
c=2
Log base 2 of 4 obvioussly the answer is 2, but
2^3 /= (does not equel) 3 x 2.
i dont' know how to make sense of this discrepency. i imagine I'm just reading it wrong.
 
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  • #2
hmmm the right formula is [tex]log_c(a)^b=blog_c(a)[/tex]

edit: heh, I am tired =P
 
Last edited:
  • #3
because [tex](c^a)^b=c^{a*b}[/tex].
 
Last edited:
  • #4
Actually the correct formula is:

[tex]\log_c(a^b) = b\log_c (a)[/tex]

This can be proven by taking the base c exponential of each side:

[tex]c^{\log_c(a^b)} = a^b[/tex]

[tex]c^{b\log_c (a)} = (c^{\log_c (a)})^b= (a)^b[/tex]
 

1. What are the basic properties of logarithms?

The basic properties of logarithms include the product property, quotient property, power property, and change of base property.

2. How do I simplify logarithmic expressions?

To simplify logarithmic expressions, you can use the basic properties of logarithms to manipulate the expression into a simpler form.

3. What is the difference between natural logarithms and common logarithms?

Natural logarithms use a base of e, while common logarithms use a base of 10. This means that natural logarithms are typically used in mathematical and scientific calculations, while common logarithms are more commonly used in everyday situations.

4. Can logarithmic properties be used to solve exponential equations?

Yes, logarithmic properties can be used to solve exponential equations by taking the logarithm of both sides of the equation and using the power property to manipulate the equation into a simpler form.

5. Are there any restrictions on the values that can be used in logarithmic properties?

Yes, logarithmic properties can only be applied to positive real numbers. This means that the number inside the logarithm (known as the argument) must be greater than 0.

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