" Life is not a problem to be solved but a reality to be experienced! "
© Copyright 2013 - 2024 KUDO.TIPS - All rights reserved.
cos(2x) = 2cos²(x) - 1
3(cos(2x)) = 6cos²(x) - 3
6cos²(x) + cos(x) - 2 - 3 = 0
6cos²(x) + cos(x) - 5 = 0
Hacemos u = cos(x) nos queda.
6u² + u - 5 = 0.
donde a = 6; b = 1; c = -5
U1 = (-1 +11)/12 = 5/6
U2 = (-1 -11)/12 = -1
como u = cos(x)
cos(x) = 5/6
cos(x) = -1
arccos es cos^-1
arccos(5/6) = 33.557°
arccos(-1) = 180°
Los angulos que cumplen son 33.557° y 180°