Is this right?

Question

(3 points )If A  B and B  C, what can you conclude? Why? What if A  B and B  C? If A  B and B  C?

Because subsets are transitive (meaning that all the members of B are also in C and all the members of A are also in B, therefore all the members of A are also in C).

If AB and B  C, then A  C, because subsets are transitive.

If A  B and B  C, then A  C, because subsets are transitive.


(4 points) Write down all possible subsets of {a, b, c, d}

{a,b,c,d}, {a,b,c}, {a,b,d}, {b,c,d}, {a,c,d}, {a,b}, {a,c}, {a,d}, {b,c}, {b,d}, {c,d}, {a}, {b}, {c}, {d}, { }.
16 sets


(2 points) Without writing them down what are the number of subsets of the set A = {a, b, c, d, e, f}? Of set B = {a, b, c, d, e, f, g, h, i, j}?

number of subsets of the set A={a,b,c,d,e}? of set B = {a,b,c,d,e,f,g,h}?
number = 2^(nelts)
subsets of A = 2^5 = 32
subsets of B = 2^8 = 256

Need help:
Express the following in set-builder notation: M = {1, 2, 3, 4}

Answer 1

Deare friend,

I am powerless to help. This is way out of my league. Hope someone can help.

Addles my brain!