Register to reply

Trigonometric Proof

by likearollings
Tags: proof, trigonometric
Share this thread:
likearollings
#1
Mar15-11, 11:58 AM
P: 27
I am not quite sure how to prove this,

I can see it involves using a double angle formula (see http://mathworld.wolfram.com/Double-AngleFormulas.html).

I have tried working backwards but to no avail.

Any ideas?



Uploaded with ImageShack.us
Phys.Org News Partner Science news on Phys.org
Hoverbike drone project for air transport takes off
Earlier Stone Age artifacts found in Northern Cape of South Africa
Study reveals new characteristics of complex oxide surfaces
AlephZero
#2
Mar15-11, 01:07 PM
Engineering
Sci Advisor
HW Helper
Thanks
P: 6,929
Use
[tex]\sin a \cos b = (\sin (a+b) + \sin(a-b))/2[/itex]
likearollings
#3
Mar15-11, 01:12 PM
P: 27
Thanks! I will give that a go

likearollings
#4
Mar15-11, 01:29 PM
P: 27
Trigonometric Proof

Quote Quote by AlephZero View Post
Use
[tex]\sin a \cos b = (\sin (a+b) + \sin(a-b))/2[/itex]
Thanks, I managed to do it using

[tex]
\cos a \sin b = (\sin (a+b) - \sin(a-b))/2
[/tex]

PROBLEM SOLVED!


Register to reply

Related Discussions
Proof of trigonometric multiplication of complex numbers General Math 2
Trigonometric Identities Proof Precalculus Mathematics Homework 2
Trigonometric Proof Help Precalculus Mathematics Homework 12
Trigonometric Substitution Proof Calculus & Beyond Homework 3
Trigonometric Calculus & Beyond Homework 4