[k.s110]

I thin the answer is B...

because:

we deal with the AND before the OR, meaning we can read the equation as: \{A+B}+(A.
which can b simplified to : -
Q= A.B

am i correct?




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[sepp2k]

No, the answer is not B. I'm not quite sure what the backslash and the curly braces in your notation are supposed to represent, so I can't really tell how you came up with A.B or where you want wrong. Note though that A.B is not actually one of the options (option B is "A.not(B)")

To come up with the correct solution, the first step would be to apply De Morgan's laws to the left subexpression.

This post has been edited by sepp2k: 25 February 2013 - 06:21 PM

[k.s110]

sorry this must be my fault funny enough this is the first time i'm hearing about De Morgan's law...would this law be sufficient to simplify the whole expression?

(option B is "A.not(")

hmm...this makes me think the answer is C but i'm just throwing a wild guess..looking into De Morgans Law

sepp2k, on 25 February 2013 - 06:23 PM, said:

No, the answer is not B. I'm not quite sure what the backslash and the curly braces in your notation are supposed to represent, so I can't really tell how you came up with A.B or where you want wrong. Note though that A.B is not actually one of the options (option B is "A.not(")

To come up with the correct solution, the first step would be to apply De Morgan's laws to the left subexpression.

thanks for ur help =] btw

[k.s110]

k.s110, on 25 February 2013 - 06:11 PM, said:

I thin the answer is B...

because:

we deal with the AND before the OR, meaning we can read the equation as: \{A+B}+(A./>
which can b simplified to : -
Q= A.B

am i correct?




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finding it hard to use the De Morgan Law...so I found a way using truth tables but I'm still getting confused...anyone have a good tutorial or could guide me towards the answer?

[macosxnerd101]

DeMorgan's law is pretty simple: ~(A + B ) = ~A * ~B and ~(A * B ) = ~A + ~B.

[sepp2k]

De Morgan says that not(x + y) is the same as not(x).not(y). So applying that to your expression not(not(A) + not(B)), we get not(not(A)) . not(not(B)). not(not(A)) and not(not(B)) can each be simplified rather trivially and the rest is left as an exercise for the reader you.

This post has been edited by sepp2k: 26 February 2013 - 09:48 AM

[mojo666]

k.s110, it would be better to make 1 thread posting all the questions and your attempts in a single post, rather than spam multiple topics.

[k.s110]

sepp2k, on 26 February 2013 - 09:47 AM, said:

De Morgan says that not(x + y) is the same as not(x).not(y). So applying that to your expression not(not(A) + not(), we get not(not(A)) . not(not(). not(not(A)) and not(not() can each be simplified rather trivially and the rest is left as an exercise for the reader you.

The answer is therefore C...

[sepp2k]

No, it's not. You have to approach this more systematically - don't just look at the possible answers and pick the one that looks the most like what you have.

What do you end up with after simplifying not(not(A)) and not(not(B))? What does the whole expression look like now? How can you simplify that further?

This post has been edited by sepp2k: 26 February 2013 - 10:35 AM

[k.s110]

sepp2k, on 26 February 2013 - 10:34 AM, said:

No, it's not. You have to approach this more systematically - don't just look at the possible answers and pick the one that looks the most like what you have.

What do you end up with after simplifying not(not(A)) and not(not()? What does the whole expression look like now? How can you simplify that further?

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correct me if I'm wrong wouldn't it just mean I draw a truth table to simplify AB which gives D as the answer..sorry if it seem like im such a newb...at University we are learning to use truth tables and not this LAW for some reason I don't know why but the law mixed with the truth table just confused me allot...I will take your advice and try look at more systematically

[macosxnerd101]

You should read more on Boolean algebras and the basic rules you can use to simplify logical expressions. Truth tables don't scale for larger logical expressions.