--Matthew Larson Exercise 1.4 10/4/2019

-- Hypotenuse.hs
-- | A module for working with triangles.

    module Hypotenuse where

    -- | Compute the length of the hypotenuse of a triangle from the lengths
    --   of its sides.
    hypotenuse :: Double -> Double -> Double
    hypotenuse a b = sqrt (a^2 + b^2)

    -- | Square a number.

    square :: Num n => n -> n
    square x = x ^ 2

    law_of_cosines :: Double -> Double -> Double -> Double
    law_of_cosines a b gamma = sqrt (a^2 + b^2 - 2*a*b*cos(gamma*pi/180))