Question

How many elements are in the set {(a, b) | (a, b) ∈ N×N and 1 ≤ a ≤ b ≤ n}?

score 96 · Answer 1 · 2026-04-02 10:54:52

96

Views

How many elements are in the set {(a, b) | (a, b) ∈ N×N and 1 ≤ a ≤ b ≤ n}?

Published on 02 Apr 2026 - 10:54

score 387 · Answer 2 · 2026-03-20 00:06:12

387

Views

Which of these is not a subset of the powerset {0, 1}?

Published on 20 Mar 2026 - 0:06

score 241 · Answer 3 · 2026-04-01 20:47:19

241

Views

The difference of two set differences $(A-C) - (B-C)$

Published on 01 Apr 2026 - 20:47

score 52 · Answer 4 · 2026-03-25 07:46:24

52

Views

Number of set, say $A$, of subset such that $\sum |A_i|=|\xi|$ and that $A_{ij}=A_{\ell k}\iff \ell=i\land k=j$

Published on 25 Mar 2026 - 7:46

score 209 · Answer 5 · 2026-03-20 12:20:58

209

Views

Finite intersections of a countable family of sets is countable?

Published on 20 Mar 2026 - 12:20

score 315 · Answer 6 · 2026-04-10 18:32:12

315

Views

What is the set represented by [n]

Published on 10 Apr 2026 - 18:32

score 111 · Answer 7 · 2026-03-19 18:24:54

111

Views

Functions defined as Sets, and operations with them

Published on 19 Mar 2026 - 18:24

score 203 · Answer 8 · 2026-03-19 21:14:23

203

Views

how many pairs of integers

Published on 19 Mar 2026 - 21:14

score 95 · Answer 9 · 2026-04-07 06:32:36

95

Views

Proving that ${\bigcup_{n=1}^{\infty} A_n}={\bigcup_{n=1}^{\infty} B_n}$

Published on 07 Apr 2026 - 6:32

score 87 · Answer 10 · 2026-03-20 13:30:09

87

Views

Is it possible to make a bijection $ [0,1] \rightarrow[0, \infty)$?

Published on 20 Mar 2026 - 13:30

score 290 · Answer 11 · 2026-03-20 04:18:10

290

Views

Do the operations for set theory hold for classes?

Published on 20 Mar 2026 - 4:18

score 232 · Answer 12 · 2026-03-25 18:31:24

232

Views

How do I prove the distributive property of disjoint unions?

Published on 25 Mar 2026 - 18:31

score 151 · Answer 13 · 2026-03-26 14:25:16

151

Views

How do I prove that these two set of sets have this specific relationship?

Published on 26 Mar 2026 - 14:25

score 162 · Answer 14 · 2026-04-10 00:04:31

162

Views

How do I show that this relation is a partial function?

Published on 10 Apr 2026 - 0:04

score 81 · Answer 15 · 2026-03-25 18:31:28

81

Views

How do I show this property of identity functions?

Published on 25 Mar 2026 - 18:31

List Question

How many elements are in the set {(a, b) | (a, b) ∈ N×N and 1 ≤ a ≤ b ≤ n}?

Which of these is not a subset of the powerset {0, 1}?

The difference of two set differences $(A-C) - (B-C)$

Number of set, say $A$, of subset such that $\sum |A_i|=|\xi|$ and that $A_{ij}=A_{\ell k}\iff \ell=i\land k=j$

Finite intersections of a countable family of sets is countable?

What is the set represented by [n]

Functions defined as Sets, and operations with them

how many pairs of integers

Proving that ${\bigcup_{n=1}^{\infty} A_n}={\bigcup_{n=1}^{\infty} B_n}$

Is it possible to make a bijection $ [0,1] \rightarrow[0, \infty)$?

Do the operations for set theory hold for classes?

How do I prove the distributive property of disjoint unions?

How do I prove that these two set of sets have this specific relationship?

How do I show that this relation is a partial function?

How do I show this property of identity functions?

Trending Questions

Popular # Hahtags

Popular Questions