Math (please help!)
posted by noel .
1. θ is a first quadrant angle in standard position and cos 1/(sqrt10)= . Find the exact value of sin .
2. feta is a second quadrant angle in standard position and tan(feta) ((sqrt5)/2) = . Find the exact value of cos(feta) .
3. θ is an angle in standard position with domain 0° <θ< 360° and cot θ (24/7)= . Find all possible values of θ (accurate to 0.1° if necessary)

feta = β

1. draw a diagram. Legs are 1 and 3, hypotenuse is √10. If cosθ = 1/√10, sinθ = 3/√10
2. legs are √5 and 2, hypotenuse = 3. If tanθ = √5/2, cosθ = 2/3. In QII, cosθ = 2/3
3. legs are 7,24, hypotenuse =25
if cotθ < 0, θ is QII or QIV.
Arccot(24/7) = 16.26°, so
θ = 163.74° or 343.74°