Truth table and proving a tautology

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arnold28
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Homework Statement


I'm supposed to prove that this statement is a tautology (with truth table):

(p -> ((p OR q) AND ~q)) = (~p OR ~q) AND p


Homework Equations





The Attempt at a Solution



Code:
p | q | ~p | ~q | p OR q | (p OR q) AND ~q | p -> ((p OR q) AND ~q) | (~p OR ~q) | (~p OR ~q) AND p
----------------------------------------------------------------------------------------------------
1   1    0    0      1            0                      0                 0               0
1   0    0    1      1            1                      1                 1               1
0   1    1    0      1            0                      1                 1               0
0   0    1    1      0            0                      1                 1               0

But here cleary is that it is not tautology, because left side of equation gets 0 1 1 1 and right side 0 1 0 0

So where did i make mistake, because i can't see it
 
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Are you sure you have the parentheses right in the expression that is to be proven?
 
yes, it is just like that in the exercise paper
 
so do you think that I have done it right and the exercise is badly worded?