# More Trigonometric Identities

### Problems

Problem : Calculate sin(θ), cos(θ) , and tan(θ) if sin(2θ) = 2 sin(30 o )cos(30 o ) .

Problem : Calculate cos(15 o ) using the fact that cos(30 o ) = .

Problem : θ is in the first quadrant, and tan(θ) = . Find the sine, cosine, and tangent of 2θ .

Problem : θ is in the third quadrant, and sin(θ) = - . Find the sine, cosine, and tangent of (θ) .

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