Do I enter degrees or radians?

Choose the unit (degrees or radians). Default is degrees.

What about tan(90°)?

tan(90°) is undefined (division by zero). The tool shows an error or 'undefined' for such angles.

Results are decimal approximations. For 30°, 45°, 60° you get the familiar values (e.g. sin 30° = 0.5).

Get sin, cos, and tan for any angle (degrees or radians).

Angle

Radians

Do I enter degrees or radians?: Choose the unit (degrees or radians). Default is degrees.
What about tan(90°)?: tan(90°) is undefined (division by zero). The tool shows an error or 'undefined' for such angles.
Are values exact for special angles?: Results are decimal approximations. For 30°, 45°, 60° you get the familiar values (e.g. sin 30° = 0.5).

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