Show that the V : R x R → R given by (a, b) → max {a, b} and the ∧ : R x R → R given by (a, b) → min {a,b} are binary operations.
Since V carries each pair (a, b) in R x R to a unique element namely maximum of a and b lying in R, so V is a binary operation.
Similarly A carries each pair (a, b) in R x R to a unique element namely minimum of a and b lying in R, so ∧ is a binary operation.