# How do you evaluate #log_9 (1/729)#?

##### 2 Answers

#### Explanation:

In evaluating a log, read the expression as a question...

"To what power must 9 be raised to give

[Nice to know

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This actually answers the question, because there is an index of -3.

OR, using index form:

Added note in support of EZ as pi

#### Explanation:

Using example:

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Consider log to base 10

Suppose we had log base 10 of 3 written as

Set

Another way of writing this is

Set

Another way of writing this is

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Consider log to base e

Set

This is a special log which is normally written as

Another way of writing this is

Set

Another way of writing this is

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Consider log to base 9

Set

Write this as:

But

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