Question

Enter your answers as a comma-separated list. Use n as an integer constant. Enter your response in radians.

cos 7x(2 cos x + 1) = 0

Answer 1

Solve these 2 basic trig equations:
1)
a. cos 7x = 0 = cos Pi/2, and cos 3Pi/2 -> 7x = Pi/2 -> x = Pi/14 -> extended answer: x = Pi/14 + 2nPi
b. cos 7x = 0 = cos 3Pi/2 -> 7x = 3Pi/2 -> x = 3Pi/14 -> Extended answer -> x = 3pi/14 + 2n*Pi.
2) 2cos x + 1 = 0 -> cos x = -1/2 = cos 2Pi/3 and cos 5Pi/3
a. cos x = -1/2 = cos 2Pi/3 -> x = 2Pi/3 -> Extended answer: x = 2Pi/3 + 2n*Pi
b. cos x = -1/2 = cos 5Pi/3 --> x= 5Pi/3 -> extended answer -> x = 5Pi/3 + 2n*Pi.