What is the asymptote of this equation

[Jack Daniel]

Hey, I have this equation for my maths equation,
f(x)= 34990*(0.8)^x
I am assuming that the asymptote of this is y=0, would like confirmation on this.
Also would like to know, whether I would write it as y=0 or f(x)=0?
Thanks.

 

[Deleted member 4993]

Hey, I have this equation for my maths equation,
f(x)= 34990*(0.8)^x
I am assuming that the asymptote of this is y=0, would like confirmation on this.
Also would like to know, whether I would write it as y=0 or f(x)=0?
Thanks.

Why assume - when you can calculate it.

If you are asked this question as "stand alone" (i.e. when it is not a small part of much larger question), you will be expected to show calculation.

I would expect an asymptote to be expressed as an equation of a line.

 

[Jack Daniel]

I have shown working out by showing a table (attached)
If this is still incorrect, how can I express the working out?
Thanks, I will answer it as y=0 in that case


Thanks.

 

[Deleted member 4993]

I have shown working out by showing a table (attached)
If this is still incorrect, how can I express the working out?
Thanks, I will answer it as y=0 in that case. Thanks.

Do you know the mathematical definition of an asymptote?

If not - do a google search with the keyword "asymptote". Please tell us what you find. We can discuss further if you have questions.

y=0 is correct answer.

 

[Steven G]

Since y=f(x) there is no difference between y=0 and f(x)=0.

 

[Dr.Peterson]

Since y=f(x) there is no difference between y=0 and f(x)=0.

No, because in this problem f(x) refers to the given function, not to the asymptote! It is not true that f(x) = 0. It is true that the asymptote is the line y=0, which is distinct from the function itself.

I have shown working out by showing a table (attached)
If this is still incorrect, how can I express the working out?
Thanks, I will answer it as y=0 in that case

The appropriate work depends on what you have been taught about what an asymptote is.

If this were for a calculus class, you would be expected to prove something about a limit. Your context appears to be one in which you only know that the graph should approach the asymptote, and observing that trend is all the "proof" you need. I would expect that it would be sufficient to state the fact you will have been taught, that any exponential function a*b^(kx) has horizontal asymptote at y = 0.

 

[Otis]

… there is no difference between y=0 and f(x)=0.

I don't agree with that, Jomo, in this exercise. We ought to state the asymptote as y=0.

f(x)=0 means something else. It's also a false statement, in this exercise.

?

 

[Steven G]

Yes, yes, the equation of the asymptote is y=0. I guess I need some corner time for given such a poor answer.