MHB Can I Determine if a Formula is a Tautology by Finding its CNF and DNF?

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hossam killua
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find cnf and dnf
 
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my solution can't go far
 
It would be better if you used $\LaTeX$ or at least posted the images not as thumbnails, but full sized so people don't have to click on them, opening up a new tab. :D
 
This formula is a tautology.
 
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