real time - Scheduling algorithm which minimizes maximum lateness is optimal (it finds a feasible schedule, if one exists)

Question

I need to understand why if a scheduling algorithm A minimizes maximum lateness, then A is optimal (it finds a feasible schedule, if one exists).

I searched on the web for a long time, but without any success. Can you tell me which ingredients I need to prove that please?

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EDIT The viceversa is not true: if A is optimal, it can happen that A is not able to minimize the maximum lateness.

Answer 1

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