1)2arcsin(-√3/2) + 3arccos(-√2/2) = 2 · (-π/3) + 3 · 3π/4 = -2π/3 + 9π/4 = -8π/12 + 27π/12 = 19π/12
2)9¹⁻ˣ · (1/27)^-1/3 = (1/3)^7-6x
(3²)¹⁻ˣ · (3⁻³)^-1/3 = (3⁻¹)^7-6x
3²⁻²ˣ · 3 = 3⁶ˣ⁻⁷
3³⁻²ˣ = 3⁶ˣ⁻⁷
3 - 2 x = 6x - 7
-2x - 6x = - 7 - 3
-8x = -10
x = 1,25
3) 2cos(1/3 x) = √2
cos(1/3 x) = √2/2
1/3x = +-π/4 + 2πk, k ∈ Z
х = +-3π/4 + 6πk, k ∈ Z