Question 920124
(a) cos(− π/3) = cos(π/3) = 1/2
 (b) sec(− π/3) =  1/cos(π/3) = 2/1
 (c) tan(−π/3) = - tan(π/3) = -√3
Note: tanx = sinx/cosx
.....See below (cosx, sinx) Summary Unit Circle
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