Найдите cos⁡α, если sin⁡α=0,8 и 1/2 π<α<π.

Question

Найдите cos⁡α, если sin⁡α=0,8 и 1/2 π<α<π.

Answer 1

//////////////%///////////////////

---

---

---

---

Answer 2

Cos²α = 1 - sin²α ;
cos²α= 1 - 0.64 = 0.36 ;
cosα = 0.6