Byron,Fuller)question-spherical harmonics & associated legendre funct.

[knockout_artist]

Hello,

Question is about equation 5.71 ---to-----5.72

All that was done is algebra or trigonometry?
Where do I find such more example or reading or exercises.

I apologize for not printing the actual equations, there were too many symbols in them.

Thanks.

 

[knockout_artist]

Ok, so I was able to scan the book and put equation in the image.

Its is attached to this post.

Thanks

 

[SteamKing]

Well, you were able to scan most of the page. It's not clear which equations you are talking about, though.

 

[knockout_artist]

I modified the image to make it clear. Please have a look.

 

[dextercioby]

He multiplied and divided each term of the sum by sin^(|m|) \theta.

 

[knockout_artist]

Why he felt the need?
Where did he learn to manipulate equation like this? Or how can I learn it, is trigonometry or algebra?