Question

What is the domain and range of `y=log_2x`?

Answer 1

Domain: `(0,oo)`

Range: `RR`

Explanation:

First, remember that you cannot take `log(0)` and you cannot take the logarithm of a negative number and get a real number

So, `x>0 => x in (0,oo)` which is our domain

Also, by the definition of `log_2x`

`y=log_2x`

`<=>`

`2^y=x`

which is defined for all real numbers `(RR)` , which gives us our range