1. 2cos(-x) - √2 = 0 2cosx = √2 cosx = 0,5√2 х = ±π/4 + 2πn n∈Z 2. sin(x/3+П/4)=-1 x/3+π/4 = -π/2 +2πn x/3 = -π/2 +2πn - π/4 x/3 = -3π/4 +2πn x = -9π/4 +6πn n∈Z