You can put this solution on YOUR website! find the exact value of cos 23pi/12 using the properties of special triangles
Use cos half-angle identity
cos(x/2)=±√[(1+cos(x)/2]
cos(23π/12)=cos(23π/6)/2)=√[(1+cos(23π/6)/2]
For cos(23π/6) use reference angle π/6 in quadrant IV where cos>0
cos(23π/6)=cos(π/6)=√3/2
cos(23π/12)
=cos(23π/6)/2)
=√[(1+cos(23π/6)/2]
=√[(1+√3/2/2]
calculator check:
cos(23π/12)≈0.9659..
√[(1+√3/2/2]≈0.9659..
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