# Math Help - Limit

1. ## Limit

If
lim f(x)=0 calculate the following:
x→+∞

lim (f(x)+sinf⁡(x))/(f^4 (x)-2f^3 (x))
x→+∞

2. ## Re: Limit

Hey Chrisnew.

What kind of limit topics are you covering in your classes?

3. ## Re: Limit

What do you mean?

4. ## Re: Limit

If, as you seem to be saying, you have never seen a "limit" before and have no idea what to do, then you have no business attempting this problem! Chrisnew is hoping that is NOT the case and wanting to know what you do know so that we can help you.

5. ## Re: Limit

thank you but finally i found one solution i think
$\,=\,\infty\,\cdot\,-1\,=\,-\infty$

BESAUSE :
$\text{Let }a\,=\,f(x)\text{, then, as }x\text{ approaches \infty },\,a\text{ approaches 0}.$
$\lim_{a\to0}\,\frac{\sin(a)}{a}\,=\,1$

6. ## Re: Limit

Originally Posted by Chrisnew
thank you but finally i found one solution i think
$\,=\,\infty\,\cdot\,-1\,=\,-\infty$
Why do you think that is a solution. If it is, then what is the limit?

7. ## Re: Limit

i wrote the answer but i saw only mathforum.com may use ...instead of my solution

8. ## Re: Limit

Originally Posted by Chrisnew
i wrote the answer but i saw only mathforum.com may use ...instead of my solution
All I see is an answer that mathforum.com came up with. But what have you been able to do with the problem? That's what we are looking to find out. If you haven't been able to do anything then tell us. But we need to know where to start to help you out!!

-Dan