# How do you use a calculator to evaluate the expression #log2.3# to four decimal places?

##### 1 Answer

#### Answer:

It will depend upon your calculator and its built-in functions.

(see below for two examples)

#### Explanation:

**First Calculator from my desk drawer: Sharp EL-5400**

I notice that this calculator has a "log" key,

so I punch in:

and then the "log" key.

Display shows

which I round/truncate to

**Second Calculator from my desk drawer: TI BA II Plus***

I don't see a "log" button, but I do have a "ln" button

so I will need to use the change of base formula:

(remember default base for

To evaluate

To evaluate

To find