<h3>∠ACB + ∠DCB = 180° - по свойству смежных углов</h3><h3>∠АСВ = 180° - ∠DCB = 180° - 120° = 60°</h3><h3><u><em>ОТВЕТ: 60°</em></u></h3><h3><u><em /></u></h3>
1)=sin(π/18+π/9)=sinπ/6=1/2
2)=sin(π/36+35π/18)=sin71π/36=sin(2π-π/36)=-sinπ/36
(1/2)ˣ⁻² ((1/2)² + 1) > 5
(1/2)ˣ⁻² · 5/4 > 5
(1/2)ˣ⁻² > 4
(1/2)ˣ⁻² > (1/2)⁻²
x - 2 < - 2
x < 0
x∈ (- ∞ ; 0)