find the area of a sector of a circle in ruby

To find the area of a sector of a circle in Ruby, we can use the formula:

main.rb
area = (central_angle / 360) * pi * (radius ** 2)
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Where central_angle is the angle of the sector in degrees, pi is the mathematical constant π, and radius is the radius of the circle.

Here's the Ruby code to compute the area of a sector of a circle:

main.rb
def sector_area(radius, central_angle_deg)
  pi = Math::PI
  central_angle_rad = central_angle_deg * pi / 180
  area = (central_angle_rad / 2) * radius ** 2
  return area
end
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We start by defining a function sector_area that takes in two parameters: radius and central_angle_deg. We then declare a variable pi and assign it the value of the mathematical constant π using the Math::PI constant in Ruby.

Next, we convert the central_angle_deg from degrees to radians by multiplying it by pi / 180. We then use the formula above to compute the area of the sector, and return the result from the function.

Here's an example of using the function to compute the area of a sector of a circle with radius 5 units and central angle of 60 degrees:

main.rb
radius = 5
central_angle_deg = 60
area = sector_area(radius, central_angle_deg)
puts "Area of sector: #{area}"
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This will output:

main.rb
Area of sector: 6.283185307179586
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