In the reduction of Boolean satisfiability to 3-CNF satisfiability, give
the reduction of each of the following Boolean expressions.
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(a+b+c+d)*(c*d+!b)*(a*b -> c)
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!b -> ((a -> b) -> a)
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x*y -> (y*z -> !x)
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In the reduction of 3-CNF sat to the independent set problem, draw the
graph obtained from (a+b+c)*(a+!b+d)*(!d+e+!b)*(!a+!c+!d)*(b+!e+!d)