Register to reply

Integral of Sin(theta)/Sin(theta/2)

by 3uc1id
Tags: integral
Share this thread:
3uc1id
#1
Oct23-07, 03:56 AM
P: 7
The title says it all. im trying to integrate that but im not sure what substitution to use. i tried u=cos(theta/2) but something is not coming out right. does anyone have any suggestions? they would be well appriciated. thanks
Phys.Org News Partner Science news on Phys.org
Study links polar vortex chills to melting sea ice
Lab unveil new nano-sized synthetic scaffolding technique
Cool calculations for cold atoms: New theory of universal three-body encounters
cristo
#2
Oct23-07, 04:38 AM
Mentor
cristo's Avatar
P: 8,317
Can you write sin(theta) in terms of sin(theta/2)?
sutupidmath
#3
Oct23-07, 07:58 AM
P: 1,633
well, since thw OP hasn't shown up yet, i am going to make it a little bit easier for him.
Like cristo suggested you need to write sin(theta) in terms of sin(theta/2)
notice that sin(theta)=sin(2(theta/2)), now applying the double angle forumula for sin, what do we get?? like sin(x+y) = sin(x)cos(y)+cos(x)sin(y), now apply the same thing here, just notice that in our case we have x=y. Can you go from here??

3uc1id
#4
Oct24-07, 05:38 AM
P: 7
Integral of Sin(theta)/Sin(theta/2)

ok tnx. i finally got it but at the end i integrated from 0~pi. to get it.


Register to reply

Related Discussions
Mgcos(theta), mgsin(theta) Introductory Physics Homework 2
Sin(theta)theta = constant General Math 1
How to setup an integral in spherical coordinates for the volume of p = 2 sin O(theta Introductory Physics Homework 3
Easy: given theta, uncertainity on cos(theta) Introductory Physics Homework 5
Integral of cos^3 theta Introductory Physics Homework 4