The Math.acos() function returns the arccosine (in radians) of a
number, that is ∀x∊[-1;1]
Math.acos(x) = arccos(x) = the unique y∊[0;π] such that cos(y)=x
The Math.acosh() function returns the hyperbolic arc-cosine of a
number, that is ∀x ≥ 1
Math.acosh(x) = arcosh(x) = the unique y ≥ 0 such that cosh(y) = x
The Math.asin() function returns the arcsine (in radians) of a
number, that is ∀x ∊ [-1;1]
Math.asin(x) = arcsin(x) = the unique y∊[-π2;π2] such that sin(y) = x
The Math.atan() function returns the arctangent (in radians) of a
number, that is Math.atan(x) = arctan(x) = the unique y ∊ [-π2;π2]such that
tan(y) = x
The Math.atanh() function returns the hyperbolic arctangent of a number,
that is ∀x ∊ (-1,1), Math.atanh(x) = arctanh(x) = the unique y such that
tanh(y) = x
The Math.cos() static function returns the cosine of the specified angle,
which must be specified in radians. This value is length(adjacent)/length(hypotenuse).
The Math.exp() function returns e^x, where x is the argument, and e is Euler’s number
(also known as Napier’s constant), the base of the natural logarithms.
The Math.random() function returns a floating-point, pseudo-random number
in the range 0–1 (inclusive of 0, but not 1) with approximately uniform distribution
over that range — which you can then scale to your desired range.
The implementation selects the initial seed to the random number generation algorithm;
it cannot be chosen or reset by the user.
The Math.sumPrecise() function takes an iterable of numbers and
returns their sum, computed as if with infinite precision and
rounded once at the end, so it is more accurate than a naive
running sum.
The Math.tanh() function returns the hyperbolic tangent of a number, that is
tanh x = sinh x / cosh x = (e^x - e^-x)/(e^x + e^-x) = (e^2x - 1)/(e^2x + 1)