Question

Dado senx= raiz de 2 sobre 3. determine cosx

Answer 1

$sen60 = \frac{ \sqrt{3} }{2} = 60 \\ casx = \frac{ \sqrt{3} }{2} = 30 \\ casx = 30$

sen²x+cas²x=1

(√3/2)²-1=-cas²x

3/4-1=cas²x

3-4=cas²x


casx=√2

Answer 2

cos²x = 1 -sen²x
cos²x = 1 -(√2/3)²
Cos²x = 1 -(2/9)
Cos²x = 7/9
Cos x = √(7/9)
Cos x = √7 /3 ✓