Question

НАЗОВИТЕ ВСЕ ТОЧКИ
Cosx=$-frac{sqrt{2} }{2}$

Answer 1

х=±arccos(-√2/2)+2πn, nєZ.
x=±(π-π/4)+2πn, nєZ.
x=±3π/4+2πn, nєZ.

Answer 2

x = (+/-) 3π/4 + 2πn, n є Z