@3mar

Question

@3mar

study.geek.123 · Answer

Do you need help?

3mar · Answer

Well, I am here.

18jonea · Answer

i have tried to graph this and it wont allow me to

steve816 · Answer

Because you are using multiple variables.

3mar · Answer

@study.geek.123 go ahead
it is your turn!

study.geek.123 · Answer

@3mar  srry I donno yet we are literally doing this in this and the next chapter in math

study.geek.123 · Answer

in the current and the next*

steve816 · Answer

If you look at the graph, the y-intercept is NOT (0, 1).

18jonea · Answer

ok so the answer is c

steve816 · Answer

Or you can think of it like$$\log_{a} 0=1$$$$a^1\neq0$$

3mar · Answer

@study.geek.123 what you mean?

mathmale · Answer

Why not graph the most basic log function:  y=log x (whose base is 10)?  Your graph would have exactly the same shape as would $$y=\log_{b } x$$

Once you have this graph, choosing the several correct answers from the four possibilities given should become easier.

3mar · Answer

https://www.desmos.com/calculator/kjp3tbepip This is the graph of your function! Study it and deduce what it looks like!

steve816 · Answer

I am assuming that no calculator is allowed in these type of problems.

mathmale · Answer

@steve816:  Better check this!$$\log_{a} 0=1$$  Not correct.

3mar · Answer

I am assuming that calculator could be used!

mathmale · Answer

The log function is undefined when the argument is zero (0).

18jonea · Answer

c is incorrect then

mathmale · Answer

No calculator is needed here, altho' it'd be handy in obtaining a graph of the log function.  You'd be better off just learning and remembering the basic shape of that function.

3mar · Answer

$$\Huge\color{red}\checkmark$$

as it never ever touch y-axis

steve816 · Answer

@mathmale I do know! All I did was plug in 0 at first, and was trying to show him by saying that $$a^1\neq0$$

mathmale · Answer

Have you graphed the log function yet?  If not, please do so now.

18jonea · Answer

so what is the answer?

18jonea · Answer

@3mar

18jonea · Answer

3 mar posted the graph

mathmale · Answer

No fair.  YOU decide what the answers are (there are more than 1!).

18jonea · Answer

there is only one

triciaal · Answer

Think only 1 answer is FALSE

mathmale · Answer

All right...in the sense that only one of the four given answers is FALSE.  (Same response as triciaal's).

18jonea · Answer

ok c is false

3mar · Answer

$$\Huge\color{red}\checkmark$$

3mar · Answer

It'd better for A to be ]0,+oo[ as zero is not in our domain!

3mar · Answer

Thank you for the medal!
I really appreciate that!

steve816 · Answer

@3mar That is an incorrect mathematical notation. We often use the parenthesis to indicate that the domain is not included. We use brackets to indicate that it is included.

triciaal · Answer

zero is in the domain   the intercept is not 1

3mar · Answer

If x=0, then y=?? @triciaal

steve816 · Answer

@triciaal 0 is not part of the domain.

triciaal · Answer

not defined

triciaal · Answer

in addition to that read the first option

3mar · Answer

so zero is not in the domain!

steve816 · Answer

@3mar is correct. So (0, oo) is the correct form.

3mar · Answer

Yes that is what I am saying