Help me find the SIN and COS in these problems

Question

Question 1.

If ,

then  =    = 

Question 2.

If 

 = 

 

 = 

Answer 1

1) sin(-π/3) = - sinπ/3 = √3/2; cos(-π/3) = cosπ/3 = 1/2

2) sin(-11π/6 = sin(-11π/6 + 2π)= sinπ/6 = 1/2; cos(- 11π/6) = cos(-11π/6+ 2π) = cosπ/6 =√3/2