User Doug Smith

11 votes

4 answers

21k views

How would I figure out how many anagrams of mississippi don't contain the word psi?

asked Jan 30, 2013 at 14:37

6 votes

4 answers

10k views

Could someone please explain to me how (p ∨ q) = (p NAND p) NAND (q NAND q)

asked Sep 21, 2012 at 3:50

5 votes

1 answer

1k views

What are a list of helpful boolean identities for solving boolean functions?

asked Dec 16, 2012 at 23:24

4 votes

3 answers

20k views

Finding the parity check matrix for $(15, 11)$ Hamming Codes

asked Apr 1, 2013 at 10:38

4 votes

3 answers

123 views

How does this textbook go from this step to the next in proving this?

asked Dec 16, 2012 at 19:31

4 votes

1 answer

131 views

How did my professor change this logarithm into the next one? [duplicate]

asked Oct 22, 2013 at 13:30

3 votes

2 answers

13k views

How do I prove that a function grows faster than another? [closed]

asked Oct 1, 2013 at 16:13

3 votes

2 answers

1k views

Where is the value of the variable $\epsilon$ obtained in the following explanation my professor gave?

asked Oct 21, 2013 at 13:25

3 votes

3 answers

436 views

Solve $2x\equiv 18\ (\operatorname{mod} 50)$

asked Dec 17, 2012 at 17:06

3 votes

1 answer

3k views

Could anyone explain how my textbook gets this modulu congruence statement?

asked Nov 28, 2012 at 2:14

3 votes

5 answers

312 views

Find smallest number m such that $9^{32} + 19^{433} + m$ is divisible by $4$

asked Nov 28, 2012 at 3:41

3 votes

1 answer

117 views

I don't think I'm doing this function mapping question correctly, could anyone offer advice?

asked Jan 28, 2013 at 6:27

3 votes

3 answers

147 views

I'm asked to give a combinatorial proof of the following question, how would I go about doing it?

asked Jan 28, 2013 at 5:56

2 votes

2 answers

69 views

Is my answer to this combinatorics question correct? Counting the number of functions where $F(a) = F(b)$?

asked Feb 11, 2013 at 14:18

2 votes

3 answers

39k views

How to solve for the amount of arrangements of books on a shelf?

asked Jan 30, 2013 at 14:02

2 votes

2 answers

101 views

How is $\frac{x}{(1-x)^2}$ the equation for the sequence $0, 1, 2, 3, 4,\dots$

asked Feb 18, 2013 at 4:57

2 votes

1 answer

908 views

How do I calculate the cdf over this range? I'm very confused.

asked Feb 22, 2013 at 3:08

2 votes

3 answers

2k views

Find the necessary and sufficient conditions on $a$, $b$ so that $ax^2 + b = 0$ has a real solution.

asked Sep 20, 2012 at 0:49

2 votes

2 answers

67 views

New to generating functions - how do I get the function from the sequence defined by $a_n= n$ for $n\geqslant 0$?

asked Apr 18, 2013 at 16:45

2 votes

1 answer

1k views

How would I go about solving this statistics question on permutations?

asked Jan 28, 2013 at 2:29

2 votes

2 answers

534 views

If I have a vector inside a rectangle, how do I tell which side of the rectangle the vector will hit?

asked Jan 5, 2016 at 19:32

1 vote

1 answer

68 views

How does my textbook come up with this statement? I don't believe it to be true.

asked Oct 21, 2013 at 14:37

1 vote

2 answers

609 views

How does my textbook solve this summation equation for the answer?

asked Oct 22, 2013 at 2:55

1 vote

3 answers

85 views

How does my professor go from this logarithm to the following one of a different base?

asked Oct 9, 2013 at 13:15

1 vote

2 answers

95 views

How does my professor come up with the recursive case in this algorithm analysis?

asked Oct 15, 2013 at 15:01

1 vote

3 answers

324 views

Could anyone explain my prof's proof here for the induction of every natural number is congruent modulo 9 to the sum of its digits?

asked Dec 17, 2012 at 17:37

1 vote

1 answer

3k views

How do I find the number of bit strings with 3 consecutive 0s in a bit string of length n?

asked Jan 15, 2013 at 21:13

1 vote

1 answer

68 views

Did I do this probability question right?

asked Jan 21, 2013 at 23:34

1 vote

2 answers

183 views

Can someone explain what this paragraph is saying more clearly?

asked Dec 16, 2012 at 20:41

1 vote

1 answer

117 views

Could anyone explain how my textbook did this simplification?

asked Nov 6, 2012 at 23:55

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50 Questions

How would I figure out how many anagrams of mississippi don't contain the word psi?

Could someone please explain to me how (p ∨ q) = (p NAND p) NAND (q NAND q)

What are a list of helpful boolean identities for solving boolean functions?

Finding the parity check matrix for $(15, 11)$ Hamming Codes

How does this textbook go from this step to the next in proving this?

How did my professor change this logarithm into the next one? [duplicate]

How do I prove that a function grows faster than another? [closed]

Where is the value of the variable $\epsilon$ obtained in the following explanation my professor gave?

Solve $2x\equiv 18\ (\operatorname{mod} 50)$

Could anyone explain how my textbook gets this modulu congruence statement?

Find smallest number m such that $9^{32} + 19^{433} + m$ is divisible by $4$

I don't think I'm doing this function mapping question correctly, could anyone offer advice?

I'm asked to give a combinatorial proof of the following question, how would I go about doing it?

Is my answer to this combinatorics question correct? Counting the number of functions where $F(a) = F(b)$?

How to solve for the amount of arrangements of books on a shelf?

How is $\frac{x}{(1-x)^2}$ the equation for the sequence $0, 1, 2, 3, 4,\dots$

How do I calculate the cdf over this range? I'm very confused.

Find the necessary and sufficient conditions on $a$, $b$ so that $ax^2 + b = 0$ has a real solution.

New to generating functions - how do I get the function from the sequence defined by $a_n= n$ for $n\geqslant 0$?

How would I go about solving this statistics question on permutations?

If I have a vector inside a rectangle, how do I tell which side of the rectangle the vector will hit?

How does my textbook come up with this statement? I don't believe it to be true.

How does my textbook solve this summation equation for the answer?

How does my professor go from this logarithm to the following one of a different base?

How does my professor come up with the recursive case in this algorithm analysis?

Could anyone explain my prof's proof here for the induction of every natural number is congruent modulo 9 to the sum of its digits?

How do I find the number of bit strings with 3 consecutive 0s in a bit string of length n?

Did I do this probability question right?

Can someone explain what this paragraph is saying more clearly?

Could anyone explain how my textbook did this simplification?