套餐

三角函数计算器（sin、cos、tan）

输入一个角，得到它的正弦、余弦和正切。特殊角会精确显示。

结果

输入数值并点击“计算”查看结果。

公式

sin⁡θ=opphyp, cos⁡θ=adjhyp, tan⁡θ=sin⁡θcos⁡θ\sin\theta = \frac{\text{opp}}{\text{hyp}},\ \cos\theta = \frac{\text{adj}}{\text{hyp}},\ \tan\theta = \frac{\sin\theta}{\cos\theta}

SOH CAH TOA in a right triangle, extended to every angle by the unit circle.

如何使用此计算器

  1. Enter the angle and choose degrees or radians.
  2. Multiples of 30° and 45° give exact answers; other angles give rounded decimals.

例题

Trig values of 30°

sin 30° = 1/2, cos 30° = √3/2, and tan 30° = sin/cos = √3/3.

常见问题

Why is tan 90° undefined?

tan = sin/cos and cos 90° = 0, so the division is undefined.

Degrees or radians?

A full turn is 360° or 2π radians. Make sure the unit matches your problem.

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