User committedandroider

12 votes

6 answers

56k views

Is empty set element of every set if it is subset of every set?

discrete-mathematics elementary-set-theory

asked Jan 14, 2015 at 5:58

10 votes

4 answers

17k views

How can I complete this proof by contradiction?

asked Jan 16, 2015 at 23:42

6 votes

2 answers

432 views

Is this expression even a function?

functions discrete-mathematics

asked Jan 17, 2015 at 3:14

5 votes

1 answer

22k views

In this situation, based on order of operations, would cross product happen first or dot product?

matrices cross-product

asked Nov 11, 2014 at 17:58

5 votes

2 answers

4k views

Difference between "necessary" and "necessary but not sufficient"? [duplicate]

discrete-mathematics logic propositional-calculus

asked Jan 25, 2015 at 22:56

3 votes

1 answer

3k views

How to adapt proof by contradiction showing that a sqrt(2) is irrational for sqrt(20)?

discrete-mathematics logic proof-verification proof-writing

asked Jan 24, 2015 at 21:54

3 votes

1 answer

88 views

Would this be an acceptable translation of the English statement as well?

discrete-mathematics logic computer-science predicate-logic quantifiers

asked Dec 27, 2014 at 22:30

3 votes

2 answers

2k views

What does this symbol mean?

elementary-set-theory discrete-mathematics notation

asked Jan 14, 2015 at 6:43

3 votes

1 answer

99 views

Next step to reach the contradiction?

discrete-mathematics proof-verification proof-writing

asked Jan 12, 2015 at 0:07

3 votes

2 answers

2k views

Next step to take to reach the contradiction?

discrete-mathematics proof-verification proof-writing alternative-proof

asked Jan 15, 2015 at 22:03

3 votes

2 answers

4k views

How to determine which amounts of postage can be formed by using just 4 cent and 11 cent stamps? [duplicate]

discrete-mathematics proof-writing induction computer-science recursion

asked Mar 6, 2015 at 19:05

3 votes

1 answer

1k views

Can someone verify my answers to these questions regarding this poset?

discrete-mathematics elementary-set-theory logic computer-science relations

asked Mar 9, 2015 at 3:25

3 votes

0 answers

154 views

Why is this not a poset after adding zero?

discrete-mathematics elementary-set-theory computer-science divisibility relations

asked Mar 15, 2015 at 22:46

3 votes

1 answer

963 views

How to show that recurrence $T(n) \in \Omega(n^{0.5})$ using proof by induction?

discrete-mathematics recurrence-relations computer-science recursive-algorithms recursion

asked Apr 24, 2015 at 23:27

3 votes

2 answers

749 views

How to find a function that is the upper bound of this sum?

discrete-mathematics recurrence-relations asymptotics computer-science computational-complexity

asked Apr 25, 2015 at 21:50

3 votes

3 answers

861 views

Wouldn't each addition take time $O(n)$?

matrices discrete-mathematics asymptotics computer-science computational-complexity

asked May 6, 2015 at 0:11

3 votes

1 answer

654 views

Is this the correct minimum number of coins needed to make change?

discrete-mathematics computer-science recursion recursive-algorithms dynamic-programming

asked May 13, 2015 at 19:23

2 votes

1 answer

345 views

Wouldn't this Greedy Algorithm achieve the highest possible of money in this situation?

discrete-mathematics logic optimization algorithms recursive-algorithms

asked May 6, 2015 at 19:41

2 votes

2 answers

490 views

Can a relation from A to some other set B also be considered symmetric?

discrete-mathematics elementary-set-theory logic relations equivalence-relations

asked Mar 5, 2015 at 17:38

2 votes

2 answers

4k views

How to prove what amounts of postage can be formed with normal mathematical induction?

discrete-mathematics logic induction computer-science recursion

asked Mar 9, 2015 at 1:56

2 votes

2 answers

294 views

Why does a set of m elements have 2$^m$ subsets?

discrete-mathematics elementary-set-theory proof-writing computer-science relations

asked Feb 28, 2015 at 18:26

2 votes

1 answer

298 views

What is the error in this proof?

discrete-mathematics proof-verification proof-writing

asked Feb 28, 2015 at 19:35

2 votes

1 answer

268 views

How do you prove this linear algebra matrix equality?

matrices

asked Aug 16, 2014 at 7:33

2 votes

2 answers

1k views

How to start proving $A \times B \times C \ne (A \times B) \times C$?

elementary-set-theory discrete-mathematics

asked Jan 14, 2015 at 7:51

2 votes

1 answer

807 views

Why is this not a function?

functions discrete-mathematics real-numbers

asked Jan 17, 2015 at 2:12

2 votes

3 answers

20k views

Can someone verify my direct proof that if $A$ is a subset of $B$, $A\cup B = B$?

discrete-mathematics proof-verification proof-writing

asked Jan 22, 2015 at 1:20

2 votes

3 answers

4k views

How would the intersection of two uncountable sets be finite?

elementary-set-theory discrete-mathematics

asked Jan 20, 2015 at 19:31

2 votes

3 answers

2k views

How would the intersection of two uncountable sets form a countably infinite set?

discrete-mathematics

asked Jan 20, 2015 at 22:21

2 votes

1 answer

2k views

How to tell the difference between interval and coordinate notation from context?

discrete-mathematics logic real-numbers

asked Jan 25, 2015 at 6:01

2 votes

4 answers

191 views

Clarifying on how if p,q is logically equivalent to p only if q [duplicate]

discrete-mathematics logic

asked Jan 25, 2015 at 6:20

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107 Questions

Is empty set element of every set if it is subset of every set?

How can I complete this proof by contradiction?

Is this expression even a function?

In this situation, based on order of operations, would cross product happen first or dot product?

Difference between "necessary" and "necessary but not sufficient"? [duplicate]

How to adapt proof by contradiction showing that a sqrt(2) is irrational for sqrt(20)?

Would this be an acceptable translation of the English statement as well?

What does this symbol mean?

Next step to reach the contradiction?

Next step to take to reach the contradiction?

How to determine which amounts of postage can be formed by using just 4 cent and 11 cent stamps? [duplicate]

Can someone verify my answers to these questions regarding this poset?

Why is this not a poset after adding zero?

How to show that recurrence $T(n) \in \Omega(n^{0.5})$ using proof by induction?

How to find a function that is the upper bound of this sum?

Wouldn't each addition take time $O(n)$?

Is this the correct minimum number of coins needed to make change?

Wouldn't this Greedy Algorithm achieve the highest possible of money in this situation?

Can a relation from A to some other set B also be considered symmetric?

How to prove what amounts of postage can be formed with normal mathematical induction?

Why does a set of m elements have 2$^m$ subsets?

What is the error in this proof?

How do you prove this linear algebra matrix equality?

How to start proving $A \times B \times C \ne (A \times B) \times C$?

Why is this not a function?

Can someone verify my direct proof that if $A$ is a subset of $B$, $A\cup B = B$?

How would the intersection of two uncountable sets be finite?

How would the intersection of two uncountable sets form a countably infinite set?

How to tell the difference between interval and coordinate notation from context?

Clarifying on how if p,q is logically equivalent to p only if q [duplicate]