Find the domain and the equation of the vertical asymptote for the function f(x) = log(3 - x)

Question

anonymous · Answer

so I know for a log function that the domain has to be > 0

rational · Answer

thats a good start

rational · Answer

for a log function the input needs to be > 0 :

$3-x > 0$

solve $x$

anonymous · Answer

should I change it to be x < 3 since it is easier to work with than 3 - x or does it matter?

rational · Answer

yes $x \lt$ 3  is the domain

rational · Answer

wat about the vertical asymptote ?

anonymous · Answer

so why does the sign flip from 3 > x to x < 3 for the domain?

rational · Answer

3 >  x is same as x < 3

anonymous · Answer

that is what I was trying to understand

rational · Answer

suppose ur brother is taller than u

rational · Answer

saying `your brother is taller than you` is same as  saying `you are shorter than your brother`

rational · Answer

`brother >  you`


is same as :

`you < brother`

anonymous · Answer

that makes sense... thanks for explaining it

anonymous · Answer

so the vertical asymptote is set to 0?

rational · Answer

yes for vertical asymptote :

3-x = 0

x = 3