Question

Given the following function,
(a) find the domain,
(b) determine the vertical asymptote.
(c) submit the graph of the function
Please be sure to show all of your work.
y = log(-x)

Answer 1

Do you know how to use geogebra?

Answer 2

you cannot take the log of anything less than or equal to zero, so set
\[-x>0\] and solve for x in one step to get
\[x<0\] as your domain

Answer 3

if you know what
\[y=\log(x)\] looks like then
\[\log(-x)\] looks the same only rotated around the y - axis

Answer 4

mathteacher- i do not know how to use that...what is the site link?

satellite73- i know the domain of f is (-infinity, 0) U ( 0, +infinity) but not sure what the range is and what the other one is for f^-1

Answer 5

hold the phone. if the function is
\[f(x)=\log(-x)\]the domain is not what you wrote, it is
\[x<0\]

Answer 6

the domain of log is positive numbers, and if
\[-x>0\] that means
\[x<0\] for sure

Answer 7

Hi Schlowers: download geogebra here: http://www.geogebra.org/cms/en/installers It's really easy to use. Just type your function in the input bar, and press enter.

Answer 8

Also, generally speaking,

DOMAIN = "All the numbers you can put INTO a function."
RANGE = "all the numbers which come OUT OF a function."

Three things you CANNOT put in a function:
1) log of anything less than or equal to zero.
2) square root of a negative number
3) zero in the denominator

Hope this helps! :D

Answer 9

well that was wrong let me try again.
if function is
\[f(x)=\log(-x)\] domain is
\[x<0\] range is
\[\mathbb R\] and inverse depends on the base of the log. if base it ten inverse is
\[f^{-1}(x)=-10^x\] domain is
\[\mathbb R\] range is
\[y<0\]

Answer 10

if base is "e" then inverse is
\[-e^x\] and still domain is
\[\mathbb R\] range is
\[(-\infty,0)\]

Answer 11

ok so here is what i got: let me know if I am right or wrong.
(a) x < 0 or (-infinity, 0)
(b) y = log(-x)
lim log (-x)
x > 0
lim log (-x)
x > 0^-
(c) ??

Answer 12

satellite- can you tell me if my answer is correct and help me again?