SOLUTION: Find all the solutions for x to the nearest 0.01 degree in the interval [0°,360°] for the equation: cos x = -0.2108

Algebra ->  Trigonometry-basics -> SOLUTION: Find all the solutions for x to the nearest 0.01 degree in the interval [0°,360°] for the equation: cos x = -0.2108      Log On


   



Question 397432: Find all the solutions for x to the nearest 0.01 degree in the interval [0°,360°] for the equation:
cos x = -0.2108

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

cos%28x%29+=+-0.2108
arccos always returns value on interval [0, π]
x = arccos(-0.2108), 2π - arccos(-0.2108)
x = 1.783189604, or... 4.499995704
x = 1.78,...or... 4.50
Check:
cos(1.7831896041) = −0.2108,
cos(4.499995704) = −0.2108