Find the set of all real numbers α\alphaα such that cos2(α)−52cos(α)+1<0\cos^2(\alpha) - \frac{5}{2}\cos(\alpha) + 1 < 0cos2(α)−25cos(α)+1<0.
(π3,5π3)(\frac{\pi}{3}, \frac{5\pi}{3})(3π,35π)
(0,π3)∪(5π3,2π)(0, \frac{\pi}{3}) \cup (\frac{5\pi}{3}, 2\pi)(0,3π)∪(35π,2π)
(π6,11π6)(\frac{\pi}{6}, \frac{11\pi}{6})(6π,611π)
(−π3,π3)(-\frac{\pi}{3}, \frac{\pi}{3})(−3π,3π)