Question 582284:  Find all exact solutions, in radians, of: 2cos^2(x) + sqrt(2)cosx= 0... 0
Thanks heaps.  
 Answer by lwsshak3(11628)      (Show Source): 
You can  put this solution on YOUR website! Find all exact solutions, in radians, of: 2cos^2(x) + sqrt(2)cosx= 0... 0 Thanks heaps. 
** 
2cos^2(x) + √2cosx= 0 
cosx(2cosx+√2)=0 
cosx=0 
x=π/2+πn, n= integer 
or 
2cosx+√2=0 
cosx=-√2/2 
x=3π/4+2πn  and 5π/4+2πn, n=integer, in quadrants II and III where cos<0 
  | 
 
  
 
 |   
 
 |