| Blogs > Raithed |
|
Raithed
China7078 Posts
This is my takehome test that is due tomorrow. Unfortunately, I do not know how to do any of these... Explanations on how to integrals would be greatly appreciated. I am working on these on my own, and would like ideas, or someone to talk to on AIM or something to discuss how to do these. ![[image loading]](http://img134.imageshack.us/img134/2503/img001zq3.jpg)  | ||
|
fight_or_flight
United States3988 Posts
![[image loading]](http://img233.imageshack.us/img233/3386/reviewzu8.png) | ||
|
fight_or_flight
United States3988 Posts
![[image loading]](http://img138.imageshack.us/img138/483/review2fr3.png) | ||
|
Raithed
China7078 Posts
| ||
|
fight_or_flight
United States3988 Posts
| ||
|
doob10163
6 Posts
I have 1, 2, 3, 4, 6, 10, and 14 done Not quite sure how to go about the rest of these. Any ideas? | ||
|
fight_or_flight
United States3988 Posts
cos^3 = cos cos^2 = cos (1 - sin^2) then u = sin, du = 1/cos dx. For the rational ones do partial fractions. edit: also, you can use http://integrals.wolfram.com/index.jsp to check your work | ||
|
doob10163
6 Posts
i did 4 times the integral (sec^2 x) ^2 which then became sex^2 x (tan ^2x + 1) is this the right approach to be taking? If so , what is the proper next step? | ||
|
paper
13196 Posts
| ||
|
Saracen
United States5139 Posts
for 9. "which became sex^2x" ahah i see what you did there ^_^ sec^2(x)tan^2(x) function to a power times its derivative and S sec^2(x) dx = tanx well at least i'm pretty sure how it is i forgot all this shitty trig identity integration stuff | ||
|
fight_or_flight
United States3988 Posts
then its the integral of u^2 + 1 = 1/3 u^3 + u or 1/3 (tanx)^3 + tanx giving 4/3 (tanx)^3 + 4tanx | ||
|
Saracen
United States5139 Posts
right?  | ||
|
doob10163
6 Posts
| ||
|
fight_or_flight
United States3988 Posts
Basically I've just been working off my own flowchart to be honest. | ||
|
doob10163
6 Posts
| ||
|
doob10163
6 Posts
The second integral of #3 being what happens after you split the fraction and are left with 18x over the denominator | ||
|
fight_or_flight
United States3988 Posts
| ||
|
Saracen
United States5139 Posts
On April 02 2008 12:55 doob10163 wrote: Any ideas on how to do the 2nd integral of 3, 5, 11, 12, 13, 15, 16, 17, 18, and 19? The second integral of #3 being what happens after you split the fraction and are left with 18x over the denominator separate it into 2 fractions 1/(1+3x^2) and -6x/(1+3x^2) after you take out the 3 1st one is arctan 2nd one is function to a power times its derivative | ||
|
Saracen
United States5139 Posts
u-sub u=lnx du=dx/x x=e^u then use parts (tabular method) | ||
|
Saracen
United States5139 Posts
it's really straightforward...idk why it's hard? sec(theta) = sqrt(4y^2+1), dy=(sec^2(theta))d(theta)/2 | ||
| ||
StarCraft 2 StarCraft: Brood War League of Legends Counter-Strike Other Games summit1g7513 B2W.Neo807 shahzam355 byalli338 C9.Mang0230 RotterdaM192 ToD163 Liquid`Hasu158 KnowMe150 ArmadaUGS110 Trikslyr52 ViBE44 ZombieGrub33 Liquid`Ken0 |
|
Korean StarCraft League
PiG Sty Festival
Reynor vs Clem
ShowTime vs SHIN
CranKy Ducklings
OSC
SC Evo Complete
DaveTesta Events
AI Arena Tournament
Replay Cast
PiG Sty Festival
Maru vs TBD
Sparkling Tuna Cup
[ Show More ] |
|
|
EPT
