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cos

Cosine of argument in radians

Syntax

  • Y = cos(X)

Description

Y = cos(X) returns the cosine for each element of X. The cos function operates element-wise on arrays. The function accepts both real and complex inputs. For purely real values or imaginary values of X, cos returns real values in the interval [-1 ,1]. For complex values of X, cos returns complex values. All angles are in radians.

Examples

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Plot the cosine function over the domain $-\pi \leq x \leq \pi$.

x = -pi:0.01:pi;
plot(x,cos(x))
grid on

Calculate the cosine of the complex angles in vector x.

x = [-i pi+i*pi/2 -1+i*4];
y = cos(x)
y =

   1.5431 + 0.0000i  -2.5092 - 0.0000i  14.7547 +22.9637i

Input Arguments

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Input angle in radians, specified as a scalar, vector, matrix, or multidimensional array.

Data Types: single | double
Complex Number Support: Yes

Output Arguments

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Cosine of input angle, returned as a real-valued or complex-valued scalar, vector, matrix or multidimensional array.

More About

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Cosine Function

The cosine of an angle, α, defined with reference to a right angled triangle is

cos(α)=adjacent sidehypotenuse=bh.

The cosine of a complex angle, α, is

cos(α)=eiα+eiα2.

Tall Array Support

This function fully supports tall arrays. For more information, see Tall Arrays.

See Also

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Introduced before R2006a

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