Slide 1

1

2

...

(-)

: - A , B , C , . X, Y , Z ,

Friends = { , , , }Friends = {, , , }Friends = {, , , }Friends = { , , , }

F = { f, j, m, z }D = { 7, 5, 36, 19 }D = { 5, 7, 19, 36 }

?

: , A ={3,6,9,.,60}D ={1,2,22,23.,29}

? ?

: , P={1,2,3,4,.}Z ={.-2,-1,0,1,2 ..}

8741095

132456

A B

A={1,2,3,4,5}B={ 3,4,6}A{ 1,2,3,4,5}B={ 3,4,6}={1,2,3465,,,}34

abxmc

yxzmbPQPQ

A={1,2,3,4,5}B={ 3,4,6}A{ 1,2,3,4,5}B={ 3,4,6}={34,}34

A={1,2,3,4,5}B={ 3,4,6}A-{ 1,2,3,4,5}B=-{ 3,4,6}={1,25,}

A = {3,4,5}, B = {4,5,6}, P ={x,y.3,7} Q ={z,,y,7,9}. . .

A B=?

(A B)(PQ)

PQ=?

A = { 1, 2, 3 } , B = { 2, 4, 5 } C={ 4, 6, 7} ? ? 3 4 A\B=? B-C=?

U ={1,2,3,4,5,6,7}, P = {1,3,5}, Q ={2,4,6} R ={3,4,5,6,7}. . .

P-Q =?

,