In trigonometry, what is the exact value of the sine function ?

Answer and explanation

Correct answer: A.

  1. Step 1: Angle is located in the third quadrant. Step 2. In third quadrant, sine is negative: . **Answer: . Why not the others:** has wrong sign; is the cosine value.

Practise more Mathematics A: Functions, Calculus, Complex Numbers and Probability.

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