Question

Sin x/2= - корень из 2/2

Answer 1

$sin(\frac{x}{2}) = - \frac{\sqrt{2}}{2}\\\frac{x}{2} = (-1)^{k+1} * \frac{\pi}{4} + \pi*k\\x = (-1)^{k+1} * \frac{\pi}{2} + 2\pi*k$

Answer 2

sin (x/2) = - √2 /2

x/2  = (-1)ⁿ⁺¹ (π/4)  +πn , n∈ ℤ ;

x  =  (-1)ⁿ⁺¹(π/2)  + 2πn , n∈ ℤ.