# Question: let be a well formed formula let c be...

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Let α be a well formed formula; let c be the number of places at which binary connective symbols (∧, ∨, →, ↔) occur in α; let s be the number of places at which sentence symbols occur in α. (For example, if α is (A → (¬A)) then c = 1 and s = 2.) Show by using the induction principle that s = c + 1.