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Swift - cos() Function



The Swift cos() function returns trigonometric cosine of an angle (angle should be in radians). The return value will be in the range -1 through 1.

In the graph below, cos(x) vs x is plotted.

Cos Function

Syntax

In Foundation framework, it is defined as follows:

public func cos(_ x: CGFloat) -> CGFloat
public func cos(_ x: Float) -> Float
public func cos(_ x: Float80) -> Float80
public func cos(_ __x: Double) -> Double

Parameters

x Specify the angle in radian.

Return Value

Returns the trigonometric cosine of an angle.

Example:

In the example below, cos() function is used to find out the trigonometric cosine of an angle.

import Foundation

var pi = Double.pi

print("cos(pi/6) = \(cos(pi/6))")
print("cos(pi/4) = \(cos(pi/4))")
print("cos(pi/3) = \(cos(pi/3))")

The output of the above code will be:

cos(pi/6) = 0.8660254037844387
cos(pi/4) = 0.7071067811865476
cos(pi/3) = 0.5000000000000001

❮ Swift Math Functions

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