Question

Which answer represents the domain of the logarithmic function given below?

F(x) = log9 x

A. x 0
B. x < 0
C. x > 0
D. All real numbers

Answer 1

you cannot take the log of a number that is not positive

Answer 2

so find the one that says "positive numbers"

Answer 3

okay thank you

Answer 4

log9(x)=y⟺9y=x
and since 9y is always positive, that means x must always be positive

Answer 5

so it would be d? all real numbers/

Answer 6

just think about it what are these numbers are they greater or less than to each other

Answer 7

oh okay, so x is a positive number, meaning it would be greater than 0

Answer 8

Right?

Answer 9

Not necessarily it just means it isn't negative

Answer 10

D:log_{a}b \ is \ a\ \textgreater \ 0 \ \wedge \ a \neq 1 \ \wedge \ b\ \textgreater \ 0 \\ \\ D:log_{9}x \ x\ \textgreater \ 0

C.

Answer 11

so, what would i have to do to find the answer?

Answer 12

oh okay
thank you.

Answer 13

No problem!