Respuesta :

Step-by-step explanation:

[tex] \sin( \alpha ) = \frac{ \sqrt{5} }{3} \\ \alpha = 48.19 \: degrees \\ \cos( \alpha ) = \frac{2}{3} [/tex]

Answer:

cos theta =± 2/3

Step-by-step explanation:

sin theta = sqrt(5) /3

sin theta = opp side / hypotenuse

We know that

a^2 + b^2 = c^2 from the pythagorean theorem

opposite side ^2 + adjacent side ^2 = hypotenuse ^2

( sqrt(5)) ^2 +   adjacent side ^2  = 3^2

5 +  adjacent side ^2  = 9

Subtract 5 from each side

5-5 +  adjacent side ^2  = 9-5

 adjacent side ^2  = 4

Taking the square root of each side

 adjacent side   = ±2

We know that

cos theta = adj side / hyp

cos theta =± 2/3