Question

Find the union and intersection of the following families or indexed collections.

Answer 1

i would like to help

Answer 2

please help!

Answer 3

one sec

Answer 4

lets look at examples

2N = { 1*2, 2*2, 3*2, 4*2, ... }

3N = { 1*3 , 2*3, 3*3, 4*3, ... }

5N = { 1*5, 2*5, 3*5, 4*5,... }

Answer 5

the generalized union
2N U 3N U 5N U ... = N \{1}

Answer 6

the intersection is more tricky, im helping 10 other people, see if you can find any overlap in the sets

Answer 7

the generalized union should remind you of the sieve of Eratosthenes.
2N U 3N U 5N U ... = N \{1}

Answer 8

I got it. Thanks!