# Symbolic Logic Problem

I have to determine whether or not this formal argument below is valid. If it is I have to provide a derivation of the conclusion from the premises, which I don't know how to do. If it is invalid, an interpretation which shows the invalidity must be constructed. The & signs mean "and" usually signified by a dot. The asterisk signifies a conditional (usually signified by an arrow).

(X)((LX&DX)* FX)

(EX)(DX&~FX)

__________________

~(EX)LX

https://brainmass.com/math/discrete-math/symbolic-logic-conditions-11516

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Invalid:

let ...

#### Solution Summary

A symbolic logic expression is proven to be invalid. A derivative of the conclusion from the premise is provided. Invalid interpretation are analyzed.

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