Solve the equation on the interval [0,2π) .
−5cosx=4
Select all correct solutions.
approximately 0.644
approximately 2.498
approximately 3.785
approximately 5.640
-5cos x = 4
cos x = (-4/5)
Take the arccos
arccos (-4/5) = x ≈ 2.498
Also
pi - 2.498 + pi =
2pi - 2.498 =
3.785