Prove or disprove the following predicate wffs is valid usin
     Prove or disprove the following predicate wffs is valid using derivation rules. If the predicate wff is invalid, give an interpretation that satisfy your claim.  (x)(P(x)  Q(x)) rightarrow (x)P(x)  (x)Q(x) 
  
  Solution
The given statement is TRUE
Since P(x) U Q(x) will be true only when either of P(x) is true or Q(x) is true
Hence when the PUQ is true implies either of them must be 1, therefore the given statement is TRUE

