Welcome! Log In Create A New Profile

Advanced

4(d)

Posted by slow_eddy 
Announcements Last Post
Announcement myUnisa availability 21 to 24 March 2019 03/17/2019 02:24PM
Announcement SoC Curricula 09/30/2017 01:08PM
Announcement Demarcation or scoping of examinations and assessment 02/13/2017 07:59AM
Announcement School of Computing Short Learning Programmes 11/24/2014 08:37AM
Announcement Unisa contact information 07/28/2011 01:28PM
avatar 4(d)
May 28, 2011 11:24PM
1. box (p -> q) ..... Premise. (My notation is wrong...)
2. assumption-box-1 ... box p ....... assumption. Target is -> i...
3. dotted-box ... p -> q ... box e, 1.
4. .... p ... box e, 2. << I think maybe strictly they should be in the reverse of this order?>>
5. .... q ............ -> e, 3, 4. ..... end of dotted-box
6. box q ........ box i, 3-5, 5. .........................end of assumption box.
7. box p -> box q .................... ->i, 3-6
Re: 4(d)
May 30, 2011 10:40AM
Ok, mine is exactly the same smileys with beer
avatar Re: 4(d)
May 30, 2011 12:28PM
And on the pedantic little detail of whether the p belongs on line 3 and p ->q on line 4? (Swap so in the shorthand we have the p on the "left" and "p->q" on the right). Still looks OK to me, but maybe there's some problem stating them in reverse order?

(I only mention it because we have things like the distinction between OR-i, 1 and OR-i, 2, which is purely a question of who's left and right, or equivalently "first" and "second".)

Ja.. actually this is probably best not pursued. I'm pretty sure that we'll receive reasonably lenient treatment on a point like this. If it's a matter of bare survival or getting another small plus mark, I think you one can be sure of getting it regardless of order. If by some weird conjunction of fates one ends up being a 110-per-cent-er, maybe the mark would be axed to save us from hubris.
Re: 4(d)
May 30, 2011 12:33PM
Well my p-->q is on line 3 and p is on line 4. I actually also don't think it really matters in which order. Both would seem correct
avatar Re: 4(d)
May 30, 2011 02:02PM
Yes, so is mine. (p on 3 etc)

I'm indulging in pettifoggery here. The way they write the ->e rule, the p is on the left "upstairs". That kind of suggests that it has to arrive "first". Just like a distinction is made between left and right &e.

It really doesn't matter for practical purposes, so I'll just drop the matter, like I eventually said at the end of the original. There are more important things for us to get on with.
Sorry, only registered users may post in this forum.

Click here to login