1. Find cos 105o.

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  2. Find cos (A + B) and cos (A - B) when sin A = 3/5 and A is in quadrant I and

    3. cos B = 5/13 and B is in quadrant II.

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  3. Find sin 19p

    4.               12

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  4. Prove:  sin (180o + B) = - sin B

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  5. Simplify:    tan 325o - tan 86o

    6.                1 + tan 325o tan 86o

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  6. Evaluate cos (arctan 1 + arccos x)

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  7. Solve for x:   sin (x + p/4) + sin (x - p/4) = -1

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