Simplifier les expressions suivantes
C = cos(x + π) + cos (x - π) - 2 cos (-x)
= - cos (x) - cos (x) - 2 cos (x)
= - 4 cos (x)
D = sin(x + π/2) + cos(x - π) - sin(x - π/2)
= cos (x) - cos (x) - cos (x)
= - cos (x)
E = sin (x + π) + sin(x - π) - 2 sin(- x)
= - sin (x) - sin (x) + 2 sin (x)
= - 2 sin (x) + 2 sin (x)
= 0
vous faite la suite