Respuesta :
Answer:
(a)
[tex]A\ u\ (B\ n\ C) = \{a,b,c\}[/tex]
[tex](A\ u\ B)\ n\ C = \{b,c\}[/tex]
[tex](A\ u\ B)\ n\ (A\ u\ C) = \{b,c\}[/tex]
[tex](A\ u\ B)\ n\ C = (A\ u\ B)\ n\ (A\ u\ C)[/tex]
(b)
[tex]A\ n\ (B\ u\ C) = \{b,c\}[/tex]
[tex](A\ n\ B)\ u\ C = \{b,c,e\}[/tex]
[tex](A\ n\ B)\ u\ (A\ n\ C) = \{b,c\}[/tex]
[tex]A\ n\ (B\ u\ C) = (A\ n\ B)\ u\ (A\ n\ C)[/tex]
(c)
[tex](A - B) - C = \{a\}[/tex]
[tex]A - (B - C) = \{a,b,c\}[/tex]
They are not equal
Step-by-step explanation:
Given
[tex]A= \{a,b,c\}[/tex]
[tex]B =\{b,c,d\}[/tex]
[tex]C = \{b,c,e\}[/tex]
Solving (a):
[tex]A\ u\ (B\ n\ C)[/tex]
[tex](A\ u\ B)\ n\ C[/tex]
[tex](A\ u\ B)\ n\ (A\ u\ C)[/tex]
[tex]A\ u\ (B\ n\ C)[/tex]
B n C means common elements between B and C;
So:
[tex]B\ n\ C = \{b,c,d\}\ n\ \{b,c,e\}[/tex]
[tex]B\ n\ C = \{b,c\}[/tex]
So:
[tex]A\ u\ (B\ n\ C) = \{a,b,c\}\ u\ \{b,c\}[/tex]
u means union (without repetition)
So:
[tex]A\ u\ (B\ n\ C) = \{a,b,c\}[/tex]
Using the illustrations of u and n, we have:
[tex](A\ u\ B)\ n\ C[/tex]
[tex](A\ u\ B)\ n\ C = (\{a,b,c\}\ u\ \{b,c,d\})\ n\ C[/tex]
Solve the bracket
[tex](A\ u\ B)\ n\ C = (\{a,b,c,d\})\ n\ C[/tex]
Substitute the value of set C
[tex](A\ u\ B)\ n\ C = \{a,b,c,d\}\ n\ \{b,c,e\}[/tex]
Apply intersection rule
[tex](A\ u\ B)\ n\ C = \{b,c\}[/tex]
[tex](A\ u\ B)\ n\ (A\ u\ C)[/tex]
In above:
[tex]A\ u\ B = \{a,b,c,d\}[/tex]
Solving A u C, we have:
[tex]A\ u\ C = \{a,b,c\}\ u\ \{b,c,e\}[/tex]
Apply union rule
[tex]A\ u\ C = \{b,c\}[/tex]
So:
[tex](A\ u\ B)\ n\ (A\ u\ C) = \{a,b,c,d\}\ n\ \{b,c\}[/tex]
[tex](A\ u\ B)\ n\ (A\ u\ C) = \{b,c\}[/tex]
The equal sets
We have:
[tex]A\ u\ (B\ n\ C) = \{a,b,c\}[/tex]
[tex](A\ u\ B)\ n\ C = \{b,c\}[/tex]
[tex](A\ u\ B)\ n\ (A\ u\ C) = \{b,c\}[/tex]
So, the equal sets are:
[tex](A\ u\ B)\ n\ C[/tex] and [tex](A\ u\ B)\ n\ (A\ u\ C)[/tex]
They both equal to [tex]\{b,c\}[/tex]
So:
[tex](A\ u\ B)\ n\ C = (A\ u\ B)\ n\ (A\ u\ C)[/tex]
Solving (b):
[tex]A\ n\ (B\ u\ C)[/tex]
[tex](A\ n\ B)\ u\ C[/tex]
[tex](A\ n\ B)\ u\ (A\ n\ C)[/tex]
So, we have:
[tex]A\ n\ (B\ u\ C) = \{a,b,c\}\ n\ (\{b,c,d\}\ u\ \{b,c,e\})[/tex]
Solve the bracket
[tex]A\ n\ (B\ u\ C) = \{a,b,c\}\ n\ (\{b,c,d,e\})[/tex]
Apply intersection rule
[tex]A\ n\ (B\ u\ C) = \{b,c\}[/tex]
[tex](A\ n\ B)\ u\ C = (\{a,b,c\}\ n\ \{b,c,d\})\ u\ \{b,c,e\}[/tex]
Solve the bracket
[tex](A\ n\ B)\ u\ C = \{b,c\}\ u\ \{b,c,e\}[/tex]
Apply union rule
[tex](A\ n\ B)\ u\ C = \{b,c,e\}[/tex]
[tex](A\ n\ B)\ u\ (A\ n\ C) = (\{a,b,c\}\ n\ \{b,c,d\})\ u\ (\{a,b,c\}\ n\ \{b,c,e\})[/tex]
Solve each bracket
[tex](A\ n\ B)\ u\ (A\ n\ C) = \{b,c\}\ u\ \{b,c\}[/tex]
Apply union rule
[tex](A\ n\ B)\ u\ (A\ n\ C) = \{b,c\}[/tex]
The equal set
We have:
[tex]A\ n\ (B\ u\ C) = \{b,c\}[/tex]
[tex](A\ n\ B)\ u\ C = \{b,c,e\}[/tex]
[tex](A\ n\ B)\ u\ (A\ n\ C) = \{b,c\}[/tex]
So, the equal sets are:
[tex]A\ n\ (B\ u\ C)[/tex] and [tex](A\ n\ B)\ u\ (A\ n\ C)[/tex]
They both equal to [tex]\{b,c\}[/tex]
So:
[tex]A\ n\ (B\ u\ C) = (A\ n\ B)\ u\ (A\ n\ C)[/tex]
Solving (c):
[tex](A - B) - C[/tex]
[tex]A - (B - C)[/tex]
This illustrates difference.
[tex]A - B[/tex] returns the elements in A and not B
Using that illustration, we have:
[tex](A - B) - C = (\{a,b,c\} - \{b,c,d\}) - \{b,c,e\}[/tex]
Solve the bracket
[tex](A - B) - C = \{a\} - \{b,c,e\}[/tex]
[tex](A - B) - C = \{a\}[/tex]
Similarly:
[tex]A - (B - C) = \{a,b,c\} - (\{b,c,d\} - \{b,c,e\})[/tex]
[tex]A - (B - C) = \{a,b,c\} - \{d\}[/tex]
[tex]A - (B - C) = \{a,b,c\}[/tex]
They are not equal