Алгебра 10 класс!!!
1) cost = 1/2
2) Sint= - корень 3/2
3) tgt = -1

1) cos t = 1/2, t = +- π/3 +2πn, n ∈ Z2) sin t = -√3/2, t = (-1)^(n + 1) · π/3 + πk, k∈ Z3) tg t = -1, t = -π/4 +πm, m∈ Z