1. Find cos pi/8.

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  2. The point (5, -12) is on the terminal side of A, where 0 < A < 2pi. Evaluate tan A/2.

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  3. Find sin A/2 if tan A = -2 and A lies in quadrant IV.

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  4. Evaluate cos 2A if sin A = 2/\/5.

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  5. Find sin 2A if tan A = -24/7 and A is in quadrant II.

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  6. Prove csc 2A + cot 2A = cot A

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  7. Solve:  sin 3x - sin x = 0 over 0 < x < 2p

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  8. Reduce the power of cos4x

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  9. Prove:  sec A/2  =  \/(2 + 2 cos A)

    10.                                  1 + cos A

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  10. cos 105o =


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  11. Solve for x over  0 < x < 2p :   2 cos (x/2) - sin x = 0


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  12. Prove:  sin t _ + _ sin 3t   =   tan 2t

    13.              cos t  +  cos 3t


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  13. Find the exact value of cos 195o + cos 105o


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  14.  Solve for x  over   0 < x < 2p:   sin 5x + sin 3x = 0

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