JavaScript Math.tan()
Examples
let x = Math.tan(1);
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Math.tan(0);
Math.tan(Math.PI);
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Math.tan(x) expect x in radians.
To use degrees, convert degrees to radians first.
let radians = degrees * Math.PI/180;
Math.tan(radians);
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Definition and Usage
The Math.tan() method returns the tangent of a number.
The Math.tan() method expects the number in radians.
Based on sine and cosine:
Math.tan(x) = Math.sin(x) / Math.cos(x).
What is Radians?
Radians is an angle's α amount of rotation b on a circle:
| Degrees | PI | Radians |
|---|---|---|
| 0° | 0 | 0 |
| 1° | PI/180 | 0.0175 |
| 30° | PI/6 | 0.52 |
| 45° | PI/4 | 0.79 |
| 90° | PI/2 | 1.57 |
| 180° | PI | 3.14 |
| 360° | PI*2 | 6.28 |
JavaScript Tangent Methods:
The Math.tan() MethodThe Math.tanh() Method
The Math.atan() Method
The Math.atan2() Method
The Math.atanh() Method
Sine and Cosine Methods:
The Math.sin() MethodThe Math.cos() Method
Syntax
Math.tan(x)
Parameters
| Parameter | Description |
| x | Required. A number representing radians. |
Return Value
| Type | Description |
| Number | The tangent of the number.NaN if the number is empty or not numeric. |
The Pythagoran Therorem
Math.sin(), Math.cos(),
and Math.tan() are related to the Pythagorean theorem:
Theorem: c2 = a2 = b2
The sine Math.sin() to the angle is a / c.
The cosine Math.cos() to the angle is b / c.
The tangent Math.tan() to the angle is a / b.
Browser Support
Math.tan() is an ECMAScript1 (ES1) feature.
ES1 (JavaScript 1997) is fully supported in all browsers:
| Chrome | IE | Edge | Firefox | Safari | Opera |
| Yes | Yes | Yes | Yes | Yes | Yes |
