March 11th, 2011, 09:33 AM  #1 
Member Joined: Feb 2009 Posts: 54 Thanks: 0  Solve equation All Ive got so far is 
March 11th, 2011, 10:25 AM  #2 
Global Moderator Joined: Nov 2009 From: Northwest Arkansas Posts: 2,766 Thanks: 4  Re: Solve equation
So far, so good. Now replace sin^2(x) with 1  cos^2(x) in both places, and you should get a quadratic equation "in cos(x)". ie, if you sub U = cos(x), you'll be able to rewrite as aU^2 + bU + c = 0 and solve by usual methods. 
March 11th, 2011, 06:47 PM  #3 
Senior Member Joined: Apr 2007 Posts: 2,140 Thanks: 0 
Tank271, this should be very easy to solve if you know the trigonometric identities cos 2x = cos²x  sin²x and sin²x + cos²x = 1.


Tags 
equation, solve 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Solve the Equation for X  Shamieh  Algebra  6  May 21st, 2013 09:46 PM 
solve equation  mmmmxxx  Algebra  3  September 4th, 2012 06:22 PM 
Solve the equation...  boomer029  Algebra  8  March 17th, 2012 05:09 PM 
Solve the equation indicated  ishoothigh  Algebra  1  December 14th, 2011 08:09 AM 
solve this equation for x  sagelady  Calculus  2  July 24th, 2011 08:35 PM 