9000046509

SubArea: 
Trigonometric equations and inequalities
Level: 
B
Project ID: 
9000046509
Source Problem: 
2010014905
Accepted: 
1
Clonable: 
1
Easy: 
1
Identify the optimal first step convenient to solve the following trigonometric equation. Do not consider the step which is possible but does not help to solve the equation. 2cos2⁡x=sin⁡x+1
2−2sin2⁡x=sin⁡x+1
substitution sin⁡x+1=z
substitution cos⁡x=z
2cos2⁡x=1−sin2⁡x+1