How do I change the base of a logarithm in the calculator?

For example, if I want to calculate log_{3}(5), how do I set my logarithm base to 3?

Guest Aug 27, 2019

#1**+2 **

On our calculator, type

log (5, 3) and hit the " = " key

This is the evaluation of log _{3} 5

CPhill Aug 27, 2019

#2**+2 **

um, CPhill is answering it and I'm sure his answer is more qualified.

But, you would basically put the normal log_2(5) on the numerator and log_2(3) on the denominator which is:

\(\frac{log_2(5)}{log_2(3)} \\OK\ so\ I\ used\ the\ change\ of\ base\ formula\ to\ do\ this... \\ \frac{log(5)}{log(3)} (simplify)\)

And you would enter that into your calculator.

(log(5))/(log(3))

But if you want to find out more about the change of base formula, I would suggest KhanAcdemy if you are not familiar with it...

link:

https://www.khanacademy.org/math/algebra2/x2ec2f6f830c9fb89:logs/x2ec2f6f830c9fb89:change-of-base/a/logarithm-change-of-base-rule-intro

tommarvoloriddle Aug 27, 2019

edited by
tommarvoloriddle
Aug 27, 2019

edited by tommarvoloriddle Aug 27, 2019

edited by tommarvoloriddle Aug 27, 2019

edited by tommarvoloriddle Aug 27, 2019

edited by tommarvoloriddle Aug 27, 2019

#3**+2 **

Your answer is as good as mine, Tom.....the change-of-base works well, too.....

CPhill
Aug 27, 2019

#4**+2 **

The title was the change of base...

So I thought it was something like that

tommarvoloriddle
Aug 27, 2019