Question

how do i construct a truth table from this statement Q->~R i was trying to make an arrow there. help!!!!!!!!!!!

Answer 1

use mathe matical reasoning.

Answer 2

the statement would be (p v ~q) iff p
which would be read like that: (p or not q) if and only if p

First of all, to construct a truth table you need to know what values each connective would give (the connectives are: ~, v, iff)
1) ~p produces a value of true if its operand is false and a value of false if its operand is true. In other words, it has the oposite value of its operand (which is q in your case).
2) p v q produces a value of true if and only if at least one of its operands is true.
3) p iff q produces a value of true if and only if both operands are false or both operands are true.

Now that you know these rules, constructing the truth table would be really easy.

p....q....~q.... (p v ~q)... (p v ~q) iff p
T....T..... F.........T.............T
T....F.... T..........T.............T
F....T..... F.........F.............T
F....F.....T..........T.............F

Hope I was able to help!
Good Luck :)