# How do you evaluate #log100#?

##### 2 Answers

Aug 22, 2016

2

#### Explanation:

Using the

#color(blue)"law of logarithms"#

#color(red)(|bar(ul(color(white)(a/a)color(black)(log_b a=nhArra=b^n)color(white)(a/a)|)))# When the log without any base indicated,is used, it usually assumes base 10.

#rArrlog_10 100=nrArr100=10^nrArrn=2#

Aug 22, 2016

#### Explanation:

A log expression asks a question....

If no base is shown, it is assumed to be 10

In this case

"What power of 10 is 100?"

"100 is which power of 10?"

"Which index of 10 will make 100?"

Log form and index form are interchangeable.

We know that

IN the same way: