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sara12345 Group TitleBest ResponseYou've already chosen the best response.0
dw:1348907509327:dw
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
if 'a', then 'b' : a> b
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
is that correct ?.. can i write teh same as, only if 'b', then 'a' ?
 2 years ago

badreferences Group TitleBest ResponseYou've already chosen the best response.0
Are you asking if you can reverse "if A, then B" to "if B, then A"?
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
no, the thing troubling me is "only if"
 2 years ago

badreferences Group TitleBest ResponseYou've already chosen the best response.0
That doesn't sound right. "Only if" B still has many things that aren't A.
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
actually i dont get "if and only if", im trying to understand it by breaking it down to "if" and "only if"
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
may i knw why it doesnt sound right to you, it does sound right to me
 2 years ago

badreferences Group TitleBest ResponseYou've already chosen the best response.0
But... a square is a kind of a rectangle.
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
dw:1348907860375:dw
 2 years ago

badreferences Group TitleBest ResponseYou've already chosen the best response.0
"A square cannot be a rectangle"?
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
excuse me, my question is different, plz look at the diagram what im asking
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
only if its b, then only it can be a
 2 years ago

badreferences Group TitleBest ResponseYou've already chosen the best response.0
"In Euclidean plane geometry, a rectangle is any quadrilateral with four right angles." "In geometry, a square is a regular quadrilateral. This means that it has four equal sides and four equal angles (90degree angles, or right angles)." So a square shares all the properties of a rectangle, but has the additional condition that it's regular. So all squares are rectangles.
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
a doesnt have any possibility outside b
 2 years ago

badreferences Group TitleBest ResponseYou've already chosen the best response.0
No, but just because it's B doesn't necessarily mean it's A.
 2 years ago

badreferences Group TitleBest ResponseYou've already chosen the best response.0
Replace A with "it rained last night" and B with "the grass was wet the next morning".
 2 years ago

badreferences Group TitleBest ResponseYou've already chosen the best response.0
There are many ways for the grass to be wet the next morning (dew, sprinklers), even if it raining last night necessarily means that the grass is wet next morning.
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
@UnkleRhaukus you got me correctly! 3rd point in ur snapshot says it
 2 years ago

badreferences Group TitleBest ResponseYou've already chosen the best response.0
Ahh, okay, the third point. I thought you were saying something else. My bad.
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
its okay... i dont get "if and only if" could you walk me through slowly plz
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
ive understood "only if" i guess, whats "if and only if", i mean i knw it means, a iff b is same as a>b, b>a
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
but why it is called "if and only if" is confuses me
 2 years ago

UnkleRhaukus Group TitleBest ResponseYou've already chosen the best response.2
\[\begin{array}{ccccc}\phi&\psi&\phi\Rightarrow\psi&\phi \Leftarrow\psi&\phi\Leftrightarrow\psi\\ \hline \\T&T&T&T&T\\T&F&F&T&F\\F&T&T&F&F\\F&F&T&T&T\end{array}\]
 2 years ago

badreferences Group TitleBest ResponseYou've already chosen the best response.0
Unkle, is it just me, or is "only if B then A" different from "A iff B"?
 2 years ago

badreferences Group TitleBest ResponseYou've already chosen the best response.0
only if B then A is different from A if and only if B.
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
im familiar with xnor truth table, but still why its called "if and only if" should we break it into two : 1) if, 2) only if
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
a iff b break as : if a then b, a only if b ?
 2 years ago

zzr0ck3r Group TitleBest ResponseYou've already chosen the best response.0
@sara12345 do you understand if a then b?
 2 years ago

UnkleRhaukus Group TitleBest ResponseYou've already chosen the best response.2
if and only if \(\Leftrightarrow\) iff
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
yes, i understood iff also, only the "phrase" is confusing me
 2 years ago

zzr0ck3r Group TitleBest ResponseYou've already chosen the best response.0
I think I'm confused about what your asking. Sorry.
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
sorry, like a iff b can i break it into 2 pieces : 1) if a then b, 2) a only if b ?
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
the two broken statements, do they cover completely "a iff b" ?
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
il start over.
 2 years ago

UnkleRhaukus Group TitleBest ResponseYou've already chosen the best response.2
these statements say the same thing 1) if a then b, 2) a only if b _______
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
ohh yea they say same thing, a>b
 2 years ago

UnkleRhaukus Group TitleBest ResponseYou've already chosen the best response.2
to meant the same as a iff b switch the letters around in one of them
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
so hw can iu break it meanigfully
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
a "if and only if " b : a <> b a "if" b : b>a a "only if" b : a>b i guess now i have it working in above
 2 years ago

sara12345 Group TitleBest ResponseYou've already chosen the best response.0
i see there is lot of difference between, "if" and "only if"
 2 years ago
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