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class method

Math.cos

Math.cos(x) → float

static VALUE
math_cos(VALUE unused_obj, VALUE x)
{
    return DBL2NUM(cos(Get_Double(x)));
}

Returns the cosine of x in radians.

Domain: (-INFINITY, INFINITY).
Range: [-1.0, 1.0].

Examples:

Example

cos(-PI)   # => -1.0
cos(-PI/2) # => 6.123031769111886e-17 # 0.0000000000000001
cos(0.0)   # => 1.0
cos(PI/2)  # => 6.123031769111886e-17 # 0.0000000000000001
cos(PI)    # => -1.0

See also .cbrt .cosh .atanh .erf also in 4.1 · 4.0 · 3.4 · 3.3 · 3.1 · 3.0

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