| 
 
 
| Question 775359:  find all exact solutions to the equation on [0,2 pi): 2 sin^2u= 1-sinu
 Answer by htmentor(1343)
      (Show Source): 
You can put this solution on YOUR website! First move all the terms to LHS: 2sin^2(u) + sin(u) - 1 = 0
 If we let x=sin(u), this gives
 2x^2 + x - 1 = 0
 This can be factored as (2x-1)(x+1) = 0
 This gives x = 1/2, x = -1, or sin(u) = 1/2, sin(u) = -1
 (Or we could have completed the factoring in terms of sin(u) directly)
 I'll leave it as an exercise for you to determine the values of u.
 
 | 
  
 | 
 |