Find all real numbers that satisfy the equation cos x squar

Find all real numbers that satisfy the equation. cos x = squareroot 3/2 Select the correct choice below and fill in the answer boxes within your choice. A. The solution set is {x|x = + 2k pi or x = + 2k pi}, where k is any integer. (Type an exact answer, using pi as needed. Type any angles in radians between 0 and 2 pi. Use ascending order.) B. The solution set is {x|x = + k pi or x = + k pi}, where k is any integer. (Type an exact answer, using pi as needed. Type any angles in radians between 0 and 2 pi. Use ascending order.) C. The solution set is {x|x = + k pi/2 or x = + k pi/2}, where k is any integer. (Type an exact answer, using pi as needed. Type any angles in radians between 0 and 2 pi. Use ascending order.) D. There is no solution.

Solution

cosx = sqrt(3)/2

x = cos^-1(sqrt(3)/2)

cos is +ve in Ist and IVrth quadrant

x = pi/6 ; x= 2pi -pi/6 = 11pi/6

General solution : x= 2kpi +pi/6 ; x= 2kpi+ 11pi/6