Proof and Problem Solving - Relations Example 01

A concrete example of working with relations. The sets A, B, and C are defined as A = {1,2,3}, B = {4, 5, 6}, and C = {7, 8, 9}. The relation R is from A to B and is defined as R = {(1,4), (1,5), (2,6), (3,6)}. The relation S is from B to C and is defined as S = {(4,7), (5,8), (6,9)}. The relation T is from A to C and is defined as T = {(1,7), (1,8), (2,7),
(3,8), (3,9)}.

We compute the composition of S and R, as well as the composition of R and inv(T).

[sheelawate]

God bless you and your family thanks....

[sudharsanad]

It's really helpful..thank u very much for your nice explanation..i am lucky to catch ur video...

[amrutapandhare]

what if we have (3, 4) but there's no any element that start with 4 ?

[daniellematzick]

OMG! This makes SO much more sense now. Thank you!!!

[Dipak_Gohil]

You taught better then our faculty..👍👍

[ignassablinskas]

In the second example you want to find R o T^-1, but along the way you write it was T^-1 o R, is this a mistake?

[lesliejarweilei]

what if there are repeats in the 's composed of r' column? do we only write them once in the final answer?

[rishabhgeete]

I have 0 in the s relation what to do??

[nurhayatimawi]

nice video. but I have a question sir. for example for question 2, if we write the answer (4, 7), (5, 7).... Is it acceptable? it is the arrangement of the number is not important? Thank you.

[yangying]

Finally i found a good video to learn discrete mathematics. Very clear and easy to understand.

[Max-xmjk]

Holy cow... I had a BIG trouble with understanding composite and inverse relations. You made it so easy... i feel like a dimwit for not understanding this. THANKS!

[mcashkettchum]

finally understood the concept. Thanks a ton!

[brookswilliams]

Nice, I like examples much better. My textbook doesn't use many.

[o]

Thanks for the example, this helped a lot.

[estebanlopez]

thanks a million Adam, you are the fucking man