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More Trigonometric Identities Problems 2

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Topics More Trigonometric Identities Problems 2

Problem : Use α = 30^o and β = 45^o to find the sine, cosine, and tangent of 75^o.

sin(75^o) = sin(30^o +45^o) = sin(30^o)cos(45^o) + cos(30^o)sin(45^o)

0.9659. cos(75^o) = cos(30^o +45^o) = cos(30^o)cos(45^o) - sin(30^o)sin(45^o)

0.2588. tan(75^o) = tan(30^o +45^o) =

3.732.

Problem : Use α = 135^o and β = 30^o to find the sine, cosine, and tangent of 105^o.

sin(105^o) = sin(135^o -30^o) = sin(135^o)cos(30^o) - cos(135^o)sin(30^o)

0.9659. cos(105^o) = cos(135^o -30^o) = cos(135^o)cos(30^o) + sin(135^o)sin(30^o)

- 0.2588. tan(105^o) = tan(135^o -30^o) =

- 3.732.

Problem : Express the following as a function of a single angle: sin(20^o)sin(30^o) + cos(20^o)cos(30^o).

cos(- 10^o)

Problem : Express the following as a function of a single angle: .

tan(72^o)

Problem : Express the following as a function of a single angle: sin(340^o)cos(120^o) + cos(340^o)sin(120^o).

sin(460^o) = sin(100^o).

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