Daca x € (π, 2π) si cos de x = 7/25 sa se calculeze sin x

Daca x € (π, 2π) si cos de x = 7/25 sa se calculeze sin x.

x € (- ∞, +∞)

cos x = 7/25

sin x = ?

Rezolvare

cos²x + sin²x = 1

sin²x = 1 - cos²x

sin²x = 1 – (7/25)²

sin²x = 1 – 49/625

sin²x = (625 – 49)/625

sin²x = 576/625

sin x = √(576/625)
sin x = 24/25

Exercitii rezolvate clasa a 9 a

Probleme si exercitii rezolvate