Step 1: $A \to (B \to A) \equiv \sim A \vee (\sim B \vee A) \equiv (\sim A \vee A) \vee \sim B \equiv T \vee \sim B \equiv T$.
Step 2: $A \to (A \vee B) \equiv \sim A \vee (A \vee B) \equiv (\sim A \vee A) \vee B \equiv T \vee B \equiv T$.
Step 3: Since both are tautologies, they are equivalent.