SOLUTION: Find all solutions if 0° &#8804; &#952; < 360°. Verify your answer graphically. (Enter your answers as a comma-separated list.) cos 3&#952; = 1 3&#952; = 0°+360°k (3&#952;)/

Algebra ->  Trigonometry-basics -> SOLUTION: Find all solutions if 0° &#8804; &#952; < 360°. Verify your answer graphically. (Enter your answers as a comma-separated list.) cos 3&#952; = 1 3&#952; = 0°+360°k (3&#952;)/      Log On


   



Question 1005216: Find all solutions if 0° ≤ θ < 360°. Verify your answer graphically. (Enter your answers as a comma-separated list.)
cos 3θ = 1
3θ = 0°+360°k
(3θ)/3 = (0°+360°k)/3
θ = 0°+120°k
If k is 0 then θ = 0°
If k is 1 then θ = 120°
If k is 2 then θ = 240°
If k is 3 then θ = 360°
So shouldn't the answer be 0°, 120°, 240°, and 360°?
I thought I solved it correctly, but my answer keeps being flagged as incorrect. Any help would be greatly appreciated. Thank you

Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Your work looks good. The only trouble may be you did not pay strict attention to the inequality statement specified for the solution. 0%3C=theta%3C360 means you must exclude 360 degrees. The angle can be 0, or 120, or 240 degrees.