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How do you calculate #log_9 48# with a calculator?

Answer 1

Madelyn Anderson

Use the change of base formula with #log# or #ln# ...

You can use the change of base formula for logarithms:

#log_b a = log_c a / log_c b#

with #c=10# (common logarithm) or #c=e# (natural logarithm):

#log_9 48 = log 48 / log 9 ~~ 1.681241237 / 0.954242509 ~~ 1.761859507#

#log_9 48 = ln 48 / ln 9 ~~ 3.871291911 / 2.197224577 ~~ 1.761859507#

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Answer 2

Sadie Alexander

To calculate (\log_9 48) using a calculator:

Use the change of base formula: (\log_a b = \frac{\log_c b}{\log_c a}), where (c) can be any base.
Choose a base for logarithm that your calculator can handle, commonly base 10 or base (e) (natural logarithm).
Calculate (\log_{10} 48) or (\ln 48) using your calculator.
Calculate (\log_{10} 9) or (\ln 9) using your calculator.
Divide the result of step 3 by the result of step 4 to find (\log_9 48).

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.