Winkelsätze in ruby?

[B]Calculating More Trigonometric Functions[/B]

sin_val = Math.sin(angle)
cos_val = Math.cos(angle)
tan_val = Math.tan(angle)

# AFAIK Ruby's Math module doesn't provide acos/asin
# While we're at it, let's also define missing hyperbolic functions
module Math
 def Math.asin(x)
 atan2(x, sqrt(1 - x**2))
 end
 def Math.acos(x)
 atan2(sqrt(1 - x**2), x)
 end
 def Math.atan(x)
 atan2(x, 1)
 end
 def Math.sinh(x)
 (exp(x) - exp(-x)) / 2
 end
 def Math.cosh(x)
 (exp(x) + exp(-x)) / 2
 end
 def Math.tanh(x)
 sinh(x) / cosh(x)
 end
end

# The support for Complex numbers is not built-in
y = Math.acos(3.7)
#=> in `sqrt': square root for negative number (ArgumentError)

# There is an implementation of Complex numbers in 'complex.rb' in current
# Ruby distro, but it doesn't support atan2 with complex args, so it doesn't
# solve this problem.