2 cos theta - sqrt 3 = 0

Question

For each of the following equations, solve for (a) all degree solutions and (b) theta if 0 degrees is less than equal to theta less than equal to 360 degrees

Answer 1

Let x = theta

 

2cos(x) = √3

 

  cos(x) = √(3) / 2

 

       x = π/6

 

 

Since cosine is positive in the 1st and 4th quadrants,

 

x = 2π - (π/6)

x = 11π/6