The presenter switches from numerical examples to an algebraic proof because checking specific cases like and only verifies the statement for those particular pairs. To prove the universal statement that the product of *any* two even numbers is even, a general algebraic argument is required to cover all possible even numbers.
Conditions: The goal is to prove a universal statement about all even numbers.; Numerical examples are used only to build intuition.; Algebra is necessary for a general proof.
The presenter switches from numerical examples to an algebraic proof because checking specific cases like and only verifies the statement for those particular pairs. To prove the universal statement that the product of *any* two even numbers is even, a general algebraic argument is required to cover all possible even numbers.
Conditions: The goal is to prove a universal statement about all even numbers.; Numerical examples are used only to build intuition.; Algebra is necessary for a general proof.