burhan101 Group Title limit one year ago one year ago

1. burhan101 Group Title

$\lim_{h \rightarrow 0}\frac{ \frac{ 4 }{ 2+2h }-2 }{ h }$

2. burhan101 Group Title

|dw:1350448824402:dw|

3. mark_o. Group Title

limit approaches -2

4. burhan101 Group Title

no it approaches 0

5. terenzreignz Group Title

maybe reducing it all to just one fraction might help

6. burhan101 Group Title

|dw:1350449555332:dw| i know im doing something wrong

7. Algebraic! Group Title

find a CD in the numerator .

8. Algebraic! Group Title

$\huge \frac{ \frac{ 4-2(2+2h) }{ 2+2h } }{h }$

9. terenzreignz Group Title

$\huge \lim_{h \rightarrow 0}\frac{\frac{4}{2+2h}-2}{h}$ is the same as $\huge \lim_{h \rightarrow 0}\frac{\frac{4}{2+2h}-\frac{2(2+2h)}{2+2h}}{h}$ and further... $\huge \lim_{h \rightarrow 0}-\frac{\frac{4h}{2+2h}}{h}$

10. terenzreignz Group Title

Now reduce it to one fraction, and do any cancellations, if possible

11. burhan101 Group Title

why is it $\frac{ 4x }{ 2+2h }$

12. burhan101 Group Title

its supposed to be (2+h) *

13. terenzreignz Group Title

Looked at your first post... Ok, then $\huge \lim_{h \rightarrow 0}\frac{\frac{4}{2+h}-2}{h}$$\huge \lim_{h \rightarrow 0}\frac{\frac{4}{2+h}-\frac{2(2+h)}{2+h}}{h}$ $\huge \lim_{h \rightarrow 0}\frac{\frac{4}{2+h}-\frac{4+2h}{2+h}}{h}$

14. mark_o. Group Title

yup limit approaches to -2 as x approaches to zero

15. terenzreignz Group Title

@mark_o. You might want to reconsider..., given that there was a correction; it's 2+h, not 2+2h as was in the first post.

16. burhan101 Group Title

sorry typing error :\$

17. burhan101 Group Title

|dw:1350450481516:dw| why do i get this :S this doesnt make sense because that would mean the answer is zero

18. burhan101 Group Title

like what am i doing wrong?

19. terenzreignz Group Title

You were to multiply $\frac{2+h}{2+h}$ to the -2 in the numerator; not to the entire fraction.

20. terenzreignz Group Title

that among other things... But yeah, multiply the $\frac{2+h}{2+h}$ only to the -2, and redo your work...

21. burhan101 Group Title

but that doesnt get rid of the fraction

22. mark_o. Group Title

hmm @terenzreignz, i didnt see the first posting of 2+h, i only saw 2+2h,, ththnx for reminding though...:D

23. terenzreignz Group Title

We're not to get rid of it, only to make it simpler, ie, only one fraction bar.

24. burhan101 Group Title

|dw:1350450882525:dw| like that ?

25. terenzreignz Group Title

26. burhan101 Group Title

cross multiply?

27. burhan101 Group Title

nvm doesnt matter

28. terenzreignz Group Title

Just distribute the 2.

29. burhan101 Group Title

|dw:1350451064789:dw|

30. terenzreignz Group Title

ok... I think I know where you're getting at... Be careful, the way you wrote it is full of... difficulties. On top, you should have 4 - (4 + 2h) Groupings can make a world of difference, so you better specify which operations are prioritised...

31. terenzreignz Group Title

Not to mention you may have ignored and/or forgotten that there is another h in the denominator. Careful...

32. burhan101 Group Title

ohh alright !