Functions below returns float type number.
Return ‘e’ (the base of natural logarithms) raised to the power x.
Return the natural logarithm of x. An arithmetic error is signalled if x is less than zero.
Return the sine of angle x; x is in terms of radians.
Return the cosine of angle x.
Return the tangent of angle x.
Return the arc sine of x (the value whose sine is x), in radians.
Return the arc cosine of x.
Return the arc tangent of x.
Return the non-negative square root of x. Currently, if x is negative, an arithmetic error is signalled.
Returns x raised to the power y.
If x is negative and y is a non-integer, then an arithmetic error is signalled (mathematically should return a complex number).