Question 1118993
There is this logical equivalence, given in many tables where they include equivalences involving conditionals:

(A—>X) & (A—>Y) == A—>(X&Y) 

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So we can write
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1.  A —> (B—>D)
2.  A —> (C—>F)
3.  (A—>(B—>D)) & (A—>(C—>F))        1,2 Conjunction (CONJ)
4.  A —> ((B —> D) & (C —> F))       3 Logical equivalence
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Conditional Proof for comparison:
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1.  A —> (B —> D)            Premise
2. A —> (C —> F)             Premise
3. :: A                      Conditional Proof assumption
4. :: B —> D                 3,1 MP
5. :: C —> F                 3,2 MP
6. :: (B —> D) & (C —> F)    4,5 CONJ
7. A—>((B —> D) & (C —> F))  3-6 Conditional Proof
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