Recursive Definition of Formula Length: Learn the Basics | Logics Course Help

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ok guys this is from my logics course!

this question may be very simple but i am just gettin stuck

give a recursive definition of the length of a well formed formula that is of the number of the symbols occurring in it. For example length of (p^(~q)) is 8.
 
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OK, so if p is an atomic formula, the length is 1.
What possibilities do you have to make a new wff out of two wffs p and q?
For example, if p is a wff of length n, then (~p) is one of length n + 3.
If p and q are wff's of length n and m, respectively, then (p^q) is of length m+n+3.