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Precalculus

Course: Precalculus > Unit 2

Lesson 2: Trigonometric identities on the unit circle

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Trig identities from reflections and rotations

CCSS.Math: HSF.TF.A.3

Google Classroom

On the following unit circle, theta is in radians.

Without a calculator, evaluate the following expressions to the nearest hundredth.

Expression	Value
cosine, left parenthesis, pi, minus, theta, right parenthesis	Your answer should be an integer, like 6 a simplified proper fraction, like 3, slash, 5 a simplified improper fraction, like 7, slash, 4 a mixed number, like 1, space, 3, slash, 4 an exact decimal, like 0, point, 75 a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text
cosine, left parenthesis, 2, pi, plus, theta, right parenthesis	Your answer should be an integer, like 6 a simplified proper fraction, like 3, slash, 5 a simplified improper fraction, like 7, slash, 4 a mixed number, like 1, space, 3, slash, 4 an exact decimal, like 0, point, 75 a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text

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