p=today is monday 
q= tomorrow is wednesday 
a) p -> ~q 
b) ~(p ^ ~q) 
c) ~p v q 

p    q      a)       b)      c) 
t    t      f        t       t 
t    f      t        f       f 
f    t      t        t       t 
f    f      t        t       t 

statements b and c are equivalent 
:
In Demorgan's Law, you can think of it almost like the distributive property. with a few tweeks
:so in b) to get rid of the parenthesis you would change the p to ~p and the ~q to q  and instead of ^(and) it changes to v(or) so it becomes ~p v q . as you can see it is the same as c)  so remember the signs change much like the + and - in distribution and the  and "^" sign or the or "v" signs change from one to the other(inside and outside of the parenthesis) 

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