Home » Ask & Discuss » Mathematics. » Trignometry « Back to Discussion

Trignometry

New kid on the Block

Joined:	16 Dec 2010
Post:	23

21 Apr 2011 23:43:31 IST

0 People liked this

1371

sinC+sinD=2sin*C+D/2*cos*C-D/2

None

sinC+sinD=2sin*C+D/2*cos*C-D/2

Share this article on:

Comments (2)

hemang

Blazing goIITian

Joined: 27 Dec 2010

Posts: 1474

22 Apr 2011 11:13:05 IST

Like 0 people liked this

sinX + sinY = 2sin[ (X + Y) / 2 ]* cos[ (X - Y) / 2 ] so putting X as C and Y as D we get your you are asking for.we can prove it too. we know that sin(x+y) = sinx*cosy+cosx*sinyand sin(x-y) = sinx*cosy-cosx*siny.so putting (x) as (C+D)/2 and (y) as (C-D)/2 we get sin(x+y) + sin(x-y) = 2sinx*cosy or 2sin(C+D)/2*cos(C-D)/2 by solving we get (x+y) as 2C/2 or C. so sin(x+y0 is sinC and similarly sin(x-y) becomes 2D/2 or D. please rate me................

Banani Khuntia

New kid on the Block

Joined: 8 Feb 2012

Posts: 1

8 Feb 2012 13:27:35 IST

Like 0 people liked this

sinC+sinD=2sin*C+D/2*cos*C-D/2

Quick Reply

Reply

	Some HTML allowed.
	Keep your comments above the belt or risk having them deleted.
	Signup for a avatar to have your pictures show up by your comment
	If Members see a thread that violates the Posting Rules, bring it to the attention of the Moderator Team