Allows you to find the log of a number using any base you want

logBASE(*value*,*base*)

Press:

- ALPHA, then F2 (which is located over the WINDOW button)
- 5 or arrow keys to move down to logBASE(

or

- MATH
- A or arrow keys to move down to logBASE(

TI-84+SE with TI-OS 2.53 MP

2 byte

The `logBASE(` command is a visual upgrade to the `log(` command to compute logarithms in any base *b*. That is, the command finds the exponent that base *b* must be raised to obtain the given value.

This command can be used on both the home screen and while programming. If you are using `CLASSIC` mode, the command appears as:

```
logBASE(8,2)
3
```

But in MATHPRINT mode, this is improved to:

log_{2}(8)

3

# Formulas

The log in base *b* can also be found using the `ln(` or `log(` commands. This can be done indirectly using the change-of-base formula:

Or directly, using the optional second argument of `log(`:

```
logBASE(X,B
can be
log(X,B
```

The `logBASE(` command costs one extra byte compared to `log(`, providing only a visual improvement over its counterpart in `MATHPRINT` mode. The `log(` command is also compatible with older OS's, although its second argument is not. Both `logBASE(` and the second argument of `log(` are disabled in exam mode.

# Error Conditions

**ERR:ARGUMENT**when a base is not specified**ERR:DOMAIN**when trying to compute the logarithm of 0**ERR:NONREAL ANS**when trying to compute the logarithm of a negative number in`Real`mode

# Related Commands

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