# How do you use a calculator to evaluate the expression #log12# to four decimal places?

##### 1 Answer

#### Answer:

#### Explanation:

Since I remember (as is useful to remember):

#log 2 ~~ 0.30103#

#log 3 ~~ 0.47712125#

I can calculate:

#log 12 = log (2*2*3)#

#color(white)(log 12) = log 2 + log 2 + log 3#

#color(white)(log 12) ~~ 0.30103 + 0.30103 + 0.47712125#

#color(white)(log 12) ~~ 0.60206 + 0.47712125#

#color(white)(log 12) ~~ 1.07918125#

If you request

If we truncated this to

#1.0791#

but the following digit is

#log 12 ~~ 1.0792#

**Footnote**

If you remember good approximations for

That seems to me to be good value for the sake of remembering a couple of numbers.