Topic: Proofs (even (2k), odd(2k+1), r = a / b. etc.)

Let min(x, y) be the function whose value is the minimum of the two arguments. Use a proof by cases to show that:

min(x, min(y, z)) = min(min(x, y), z),

whenever x, y, z are real numbers.

Hint: You will need 3 cases: one for each of x, y, z assumed to be the minimum.