## jaersyn 3 years ago I need help with the bottom two integrals, top one is an example of how to do'em http://i.imgur.com/vRAvJ.jpg?1

1. jaersyn

The questions are from the partial fractions section to clue you in on how to maybe go about this

2. jaersyn

The thing is I went further into this, but it got real hectic. The answer I got for the bottom left integral was similar to the answer, but not quite, not sure where I went wrong

3. experimentX

I'll give you short answer of tan |dw:1349542124538:dw|

4. experimentX

|dw:1349542218574:dw|

5. experimentX

for the other one ... use weistrass subs ... doesn't look nice to me.

6. jaersyn

|dw:1349542371259:dw|

7. experimentX

|dw:1349542384994:dw|

8. jaersyn

Oh.. wow, see i don't have math vision like that wth. how do you even know. just you've done it so many times??

9. experimentX

I've seen it couple of times.

10. jaersyn

that's the right answer for that one, but i have to use the substitutions given, when should I sub them in?

11. jaersyn

and what is "weistrass subs"

12. experimentX

http://en.wikipedia.org/wiki/Weierstrass_substitution no matter what ... these substitutions always work ... if you can find nice answers from other method, don't use this.

13. experimentX

looks like you have simplified it so nicely ... |dw:1349542787800:dw|

14. jaersyn

what hapens to the 4?

15. jaersyn

i tried taking the 4 out so its 15/256 or something then doing the arctan thing

16. zepdrix

Buhaha, you took a picture of your notebook XD Nice handwriting at least c:

17. experimentX

yeah that would even make it nicer. |dw:1349542995485:dw|

18. jaersyn

roflmao "nice", yes.

19. jaersyn

thnx zep, it's easier for you guys to see and understand the problem that way roflmao

20. zepdrix

It's bubbly like comic sans, and it's legible XD hehe

21. jaersyn

is that right ex?

22. experimentX

should be similar to it. not sure ... try working on paper ... doing here is like playing around. i never get it right.

23. jaersyn

1/(15/256) arctan [(u+1/8)/(sqrt (15/256))]

24. jaersyn

|dw:1349543315889:dw|

25. jaersyn

a^2 = 15/256 so a is sqrt(15/256) right

26. jaersyn

i g2g now, but thanks for all your help. if anyone leaves more detailed info that'd be great, i'll be back to check.

27. jaersyn

and screw weierstrass

28. experimentX

I don't like Weierstrass either

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