Задача 45947 ...

marinichvika15

2020-04-03 21:40:30

ctg^2x+ctgx ≥ 0

sova

2020-04-04 11:43:23

★

сtgx*(ctgx+1) ≥ 0

_+__ [-1] ___ [0] __+__

ctgx ≤ -1 или ctg x ≥ 0

(-π/4)+πk ≤ x <0+πk или πk< x ≤ (π/2)+πk, k ∈ Z

О т в е т.[b] [(-π/4)+πk ;πk)U(πk; (π/2)+πk], k ∈ Z[/b]