πn,
уmin= -1, х= π+2 πn,
(π/2+2 πn;3π/2+2 πn),
n∊Z
n∊Z
n∊Z
n∊Z
n∊Z
четная
R
[-1;1]
T=2 π
[π+2πn;2π+2πn]
[2πn;
π+2πn],n∊Z
Свойства функции у = cos x.