## ksaimouli 3 years ago limit

1. ksaimouli

$\lim_{x \rightarrow {-\infty}}\frac{ 2x-1 }{ 1+2x }$

2. ksaimouli

when i divide by x i get |dw:1361724743582:dw|

3. ksaimouli

4. anonymous

OK, now what is lim x to inf of 1/x?

5. ksaimouli

plz help with this

6. ksaimouli

0

7. ksaimouli

|dw:1361724809521:dw|

8. ksaimouli

=1

9. anonymous

So you get (2-0)/(0+2)=2/2=1

10. ksaimouli

as this goes to - infin it is -1

11. ksaimouli

i mean i got -1 bu the book says it is 1

12. anonymous

No, it is not. It is always 1

13. ksaimouli

why

14. ksaimouli

as it goes to - infinity to should go to -1 right

15. anonymous

Because you end up with (2x)/(2x) = 1

16. ksaimouli

okay i got thx so no matter what after dividing we get the answer and i should not check the limit right

17. anonymous

Just try a very big neg number, say x = -100000. Then the quotiens is: -200001/-199999, which is about 1

18. anonymous

So you can even check the limit.

19. phi

I am guessing a typo in the question or the answer.

20. anonymous

@phi: me too

21. anonymous

Remember: sometimes, even books are wrong ;)

22. phi

especially math books. Proof readers miss all kinds of mistakes.

23. ksaimouli

24. anonymous

Yes, @ksaimouli , you were right all the time!

25. ksaimouli

thx

26. anonymous

YW!