# SD Logics Help

1. Nov 4, 2007

### Kwiatkowski18

My teacher threw us a couple of questions on SD that I know hardly anything about. The first one one to come up with correct answers receives an additional 10% on our next paper. I would really like to answer them all myself, but I don't have the information about SD to do them as I have never taken a Phil course regarding Logics. So please, if anyone could solve these for me, that would be wicked.

Legend: >=horeshoe = is triplebar

1. Prove that the following derivability claim holds in SD.
{(t > a) & (~t > b), a > ~l} deriviation: l > b

2. SHow that the following set of sentences is inconsistent in SD.
{(a v ~c) > ~b), ~b = (q & ~q), ~c v a}

3. Show that the members of the following pair of sentences are equivalent in SD.
a = b ~a = ~b

4. Show that the following argument is valid in SD.
(b & (e v g))
(b & g) = h
(h > f) & ~e

2. Nov 4, 2007

### Staff: Mentor

Do not post the same topic in more than one forum. We do not supply answers to schoolwork here. If you are having trouble solving a problem and show what you have done so far and where you are stuck, someone might give you suggestions on what you might do to try to solve it yourself.

I left your other thread open so that you can show what work you have done so far on each problem.