# recovery

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by , 22-May-2010 at 01:00 (83 Views)
Yes, I have a cookie and you can be in a chance to win it if you can tell me what the following is about.

(A'+B).(A+B')

Feel free to comment and discuss amognst yourself. I'm sure those specialised in the field will pick it up straight away. So let the fun happen, aye.
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Especially chocolate chip ones (hint hint, for the next time we meet )

and the ' normally means not. as in

(not A + B)+ (A + not B)

so the equation you are left with is A+B

This Is Usually involved with venn diagrams and what not :P

thats if this thing is about maths :P

Snaps
I'm going to need a definition of the . in the middle of the parenthesis, and the +.

assuming ' or ! is equal to NOT (! better be equal to NOT)
assuming + is equal to AND
leaving . to be assumed to be OR (though that's a notation I've never seen before)

(!A && B) || (A && !B)

looks like an exclusive OR or XOR, meaning that the expression is only true if either A or B are true, but is not true if both A and B are true, and is of course not true if A and be are not true

I can post the truth table to prove it, assuming that these definitions are correct. If they are not, tell me and I'll give a more correct answer.

I'd also note that since this is your location, (assuming this is true) you are simply stating you do exist at a singular unspecified location.

Hmm, unless they're vectors, the + is a vector +, the ! is a negation of the vector, which is just the (-) of it, and the . is the dot product. Then you get

-A.B + 2*A*B (where I am overloading the * operator to be a scalar multiplication in the case of 2*A and a vector multiplication in the case of A*B)
Updated 22-May-2010 at 03:10 by LBcub (another thought.)
Peachy, that is true if you take the ' as a derivative, which is common notation, but swapping a '+' for a '*' and a '.' for a '+' is very much not. Good thought, but seeing as how his notation uses (!A+B).(A+!B) instead of the ' on his location means to me that he's using set notation or at least boolean mathematics.
Peachy, I don't think you multiply them (I failed cal 2 this semester so my credentials for saying that certainly aren't high). I'm pretty sure it's A*B' PLUS B*A'

When I came in I thought it was a boolean expression similar to those encountered in discrete math but, I'm only familiar with boolean expressions as far as programming and none of the signs used are familiar to me =/
*points up at Peachy's post*

Yah, I was gonna say the product rule, too... but then I noticed that the operators (+ and *) are in the wrong places for that.

I'm stumped.
My vague memory of a bored class looking through the log book suggests it's one of De Morgan's Theorems. For calculating ANDs/ORs/etc. in different forms. Can't be botered to retrieve it to check however. :P
I've had a wee think about it, and I know the dot means multiply.

I'm fairly sure it's something to do with ratios, and possibly triangles as well... but that's as far as highschool maths takes me...
The dot can be dot product of vectors. The could either be the normal of or be normalised of the respective vector.

But It's to do with Boolean algebra, 1LB1, you hit the nail on the head of it representing exclusive OR (XOR).

Normally one would guess that + would mean OR, and . would mean AND. But it's the other way around. Why? Because then you can treat the . as multiplication and + as addition when rearranging the algebra.

the ' is NOT or ! in my location field on the forums. I only changed it because if you googled it you go to a page on boolean algebra, I tired to make it easy.