Double-Angle and Half-Angle Identities

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Double-Angle and Half-Angle Identities Use a double-angle or half-angle identity to find the exact value of each expression. 1) cos 7 π 8 2) sin 7π 8 3) sin 165 ° 4) sin 112 1 2 ° 5) sin 15 ° 6) cos 23 π 12 7) sin 22 1 2 ° 8) sin − 5π 12 9) cos 3π 8 10) sin 75 ° 11) sin θ = − 8 17 and 180 ° < θ < 270 ° Find cos θ 2 12) sin θ ...

  Glean