Math.tan() - JavaScript 编辑

The Math.tan() function returns the tangent of a number.

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The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

Syntax

Math.tan(x)

Parameters

x

A number representing an angle in radians.

Return value

The tangent of the given number.

Description

The Math.tan() method returns a numeric value that represents the tangent of the angle.

Because tan() is a static method of Math, you always use it as Math.tan(), rather than as a method of a Math object you created (Math is not a constructor).

Examples

Using Math.tan()

Math.tan(1); // 1.5574077246549023

Because the Math.tan() function accepts radians, but it is often easier to work with degrees, the following function accepts a value in degrees, converts it to radians and returns the tangent.

function getTanDeg(deg) {
  var rad = deg * Math.PI/180;
  return Math.tan(rad);
}

Specifications

Specification
ECMAScript (ECMA-262) The definition of 'Math.tan' in that specification.

Browser compatibility

BCD tables only load in the browser

See also

• Math.acos()
• Math.asin()
• Math.atan()
• Math.atan2()
• Math.cos()
• Math.sin()