Let u = {x x = k, K ∈ Z}, q = x x = 2K, K ∈ Z}, t = {x x = 2K + 1, K ∈ Z} a. The complement of q = t b. Q ∪ t is the proper subset of U c. Q is the proper subset of T d. T is the true son of Q Which of them is right and why not B

Let u = {x x = k, K ∈ Z}, q = x x = 2K, K ∈ Z}, t = {x x = 2K + 1, K ∈ Z} a. The complement of q = t b. Q ∪ t is the proper subset of U c. Q is the proper subset of T d. T is the true son of Q Which of them is right and why not B

U is an integer, q is an even number, t is an odd number
A should be chosen because an integer is either odd or even, and an odd number is not even
Q ∪ t = u in B is not a proper subset of U

Let a = {x x = 2k-1, K belongs to Z} and B = {x x = 2K, K belongs to Z} find a ∩ B

A = {x ∣ x = 2K, K ∈ Z}, then the set a is the set of all even numbers,
B = {x ∣ x = 2K + 1, K ∈ Z}, then set B is the set of all odd numbers,
A ∩ B = empty set
Do not understand welcome to ask

Let a = {x x = 2K, K ∈ Z}, B = {x x = 2K + 1, K ∈ Z}, C = {x x = 4K + 1, K ∈ Z}, if a ∈ a, B ∈ B, try to judge the relationship between a + B and set a, B, C?

(a+b)∈B

What does it mean that the intersection of set a and set B really contains an empty set

If it contains an empty set, it means it is not an empty set
That is, a ∩ B is not an empty set, or at least one element