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The unit circle

Exact values of sine and cosine at the special angles.

On a circle of radius 1, the coordinates of the point at angle θ are (cos θ, sin θ). The angles 30°, 45°, 60° and their reflections give exact values built from √2 and √3 — worth knowing by heart, and all derivable from two triangles.

작업 예제: sin(pi/3)

Arithmetic · Arithmetic

Evaluate sqrt(3)/2

\frac{\sqrt{3}}{2}

단계별로

  1. \sin{\left(\frac{\pi}{3} \right)} = \frac{\sqrt{3}}{2}

    Exact value from the unit circle: \sin{\left(\frac{\pi}{3} \right)} = \frac{\sqrt{3}}{2}.

답을 드러내세요
\frac{\sqrt{3}}{2} \approx 0.86602

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