Question 240132
express each in terms of a reference angle.? : 
1. co tangent of 285 degrees
= ctn(360-75)
= ctn(-75) = -ctn(75)
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2. secant of -105 degrees
-sec(75) 
3. co secant of 600 degrees
-csc(60) 
4. tangent of 3
= -tan(pi-3)
5. tangent of 820 degrees
= tan(820-720)
= tan(100)
= -tan(80)
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Cheers,
Stan H.