Math Union and Intersection Help?

Question

I hate these problems I cant seem to get them.

Given U = {All letters of the alphabet} A = {b, c, d} and B = {c, e, f, g} List the elements of set

(c) A′ ∩ B′ -

(d) A′ U B′ (e) A U B′
(f) (A U B′ ) ∩ B (g) (A U B) ∩ (A U B′)

Answer 1

A' = {a, e, f, g, h, i, j, k, l, m, n, o, p q, r, s, t, u, v, w, x, y, z}
(everything except b, c, and d)

B' = {a, b, d, h, i, j, k, l, m, n, o, p q, r, s, t, u, v, w, x, y, z}
(everything except c, e, f, and g)

c) A′ ∩ B′ = {a, h, i, j, k, l, m, n, o, p q, r, s, t, u, v, w, x, y, z}
(everything except b, c, d intersected with everything except c, e, f, g produces everything except b, c, d, e, f, g)

d) A′ U B′ = {a, b, d, e, f, g, h, i, j, k, l, m, n, o, p q, r, s, t, u, v, w, x, y, z}
(everything except b, c, d unioned with everything except c, e, f, g produces everything except c)

e) A U B′ = {a, b, c, d, h, i, j, k, l, m, n, o, p q, r, s, t, u, v, w, x, y, z}
({b, c, d} unioned with everything except c, e, f, g produces everything except e, f, g)

f) (A U B′) ∩ B = {c}
(everything except e, f, g intersected with {c, e, f, g} produces only c)

g) (A U B) ∩ (A U B′) = A = {b, c, d}
({b, c, d, e, f, g} intersected with everything except e, f, g produces {b, c, d}, which is A.)

Answer 2

To do things like this, first list out the components.
So A' would be {a e f g h i j k l m n o p q r s t u v w x y z}
B' would be {a b d h i j k l m n o p q r s t u v w x y z}
Also, remember that union means everything that's in either set or both, and intersection means only what they have in common.
So A' intersect B' would be what they have in common. Look at them, see what they have in common. They have most of the alphabet in common except for a few letters near the beginning.
So the intersect would be {a h i j k l m n o p q r s t u v w x y z}

Generlaly there's a lot more in a union than in an intersection.

If you hate these problems and can't seem to get them, that's probalyb because you don't understand them. There's only so much we can write here, it gets very hard to read. And when it's hard to read, it seems harder than it really is.
There are some good online explanations for just about anything you need to know in math, good graphics and clear writing can make it a lot easier to understand. To find them just type subject tutorial in your search window. For example when I put set union and intersection in my search window I get....
http://www.geocities.com/basicmathsets/setpg2.html
http://www.geocities.com/basicmathsets/
These are the first few written at a basic level. Some are written at a more advanced level, don't worry about them.
I see Jim has written out the answers for you so I don't need to do the rest of them. However, please do check out some of these sites so that you can understand these problems and get them and then you don't have to hate them any more.

Answer 3

good for the primary facet you wanna use the Multiplication Rule two of likelihood. this equation is P(A and B)= P(A) x P(B|A). Using this equation we now plug within the numbers we have now. P(A)=.four and P(B|A)=.25/ So now we multiply the 2 numbers and get .a million because the reply. For the moment facet P(A union B) is .four + .three=.7 P(A intersection B) is .four x .three= .12 P(A/B) isn't certain if they simply desire u to divide right here if this is the case then it is going to be .three/.four=.seventy five however im no longer certain approximately this one