Réponse :
167 = 156+11 = 12 * 13+11
167π /6 = 2π *13 + 11 π /6 = 11 π /6 ( modulo 2π)
ma mesure principale est 11 π /6
(u,w)=(u,v)+(v,w)= -2π/3+π/4 = -5π /12
(w;5u)=(w;u)= 5π /12
(-2w;v)=(-w;v)= (w;v) + π = - π /4 + π = 3 π/4
(AB;EF)=(AB;CD)+(CD;EF) = (AB;CD) - (EF;CD)= (AB ; CD) - ( EF;DC) + π
= π/3 + π /4 + π
= 19 π /12
mesure principale
17π/18 = 18π/18 - π/18 = π - π/18
cos17π/18 = - cosπ/18
sin(-7π/3)= sin( -2π - π/3) = sin( -π/3)= - sin(π/3)= - √3/2
Explications étape par étape
