Hi, Could someone please help me prove this identity?

sinA + sin9A = 2.sin5A.cos4A

Thanks, your help would be very much appreciated!

Printable View

- Feb 3rd 2011, 03:44 AMsammysparrowIdentity Crisis!
Hi, Could someone please help me prove this identity?

sinA + sin9A = 2.sin5A.cos4A

Thanks, your help would be very much appreciated! - Feb 3rd 2011, 04:48 AMArchie Meade
- Feb 3rd 2011, 08:07 PMsammysparrow
Thanks Archie Meade!