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#2 Re: Dark Discussions at Cafe Infinity » icelandic dictionary » 2019-06-06 04:30:38
https://www.youtube.com/watch?v=f8nQlj7Tl4o.
At 04:19 …
Ég hef enga hugmynd um hvað ég er að gera
… is Icelandic for “I have no idea what I’m doing”.
#3 Re: Puzzles and Games » First- and last-letter alphabet game » 2019-05-20 23:25:45
estate
#4 Re: Puzzles and Games » Word-morph game » 2019-05-20 23:19:24
#5 Re: Puzzles and Games » First- and last-letter alphabet game » 2019-05-20 18:08:56
characteristic
#6 Re: Puzzles and Games » Word-morph game » 2019-05-20 18:07:48
#7 Puzzles and Games » Word-morph game » 2019-05-20 17:48:45
- Alg Num Theory
- Replies: 8
Taking the word in the previous post (say it’s the word cat) do one of the following to it:
[list=1]
[*]add a letter – e.g. cat → cart[/*]
[*]take away a letter – e.g. cat → at[/*]
[*]change a letter – e.g. cat → eat[/*]
[*]move a letter – e.g. cat → act[/*]
[/list]
First word …
math
#8 Puzzles and Games » First- and last-letter alphabet game » 2019-05-20 17:31:32
- Alg Num Theory
- Replies: 25
Post an expression beginning and ending with the same letter of the alphabet: e.g. algebra, blob, civic, deed, …
We will go through the letters alphabetically.
Your expression can be a single word (e.g. extreme) or a phrase (e.g. extreme value); it can also be a proper name (including well-known fictional names) (e.g. Falstaff). It can also be in any language other than English! This should come in handy for tricky letters like J, Q and X.
Okay, first word …
algebra
#9 Re: Dark Discussions at Cafe Infinity » Did you know? » 2019-05-20 04:43:48
#29. Did you know?
There are two types of drugs: addictive (such as heroin and morphine) and non-addictive (such as marijuana). Both are dangerous in their own ways: addictive drugs lead to dependence and all the psychological and social problems that go with it, while non-addictive drugs lead the persistent user in search of increasingly bigger kicks to take more and more of them, increasing dosages to fatal levels.
I’ve just read about addiction in the medical encylcopaedia of the Reader’s Digest Family Health Guide.
#10 Re: Dark Discussions at Cafe Infinity » Giving up smoking/drinking » 2019-05-19 23:00:45
Hello Bob! 
Thanks for your words of positive encouragement. 
Personally, what I find is this. When you’re just starting on quitting something, the urge to go back to it will be very strong in the initial stages, but as time goes on this urge will decrease in intensity. I’ve read somewhere that this is possibly due to the varying amounts of a chemical called dopamine in the brain. When you’ve been used to a stimulus for a long time, withdrawing the stimulus suddenly leads to a build-up of dopamine in the brain, which causes withdrawal symptoms; as time goes on, the dopamine levels subside and so you feel less of the need for the stimulus.
So the testing time is the initial stages of quitting: this is the time you feel the strongest temptation to go back to your old habit. Once you’ve got over this initial hurdle, it will be much easier to get on with your new life without the old habit. As the character Lord Darlington in Oscar Wilde’s play Lady Windermere’s Fan says:
I couldn’t help it. I can resist everything except temptation.
So, I will keep us all posted on my progress on this resolution of mine. At the time of this post, I have not smoked for 35 hours (1 day 11 hours) continuously. For drink, it is 3 347 hours (139 days 11 hours, or 19 weeks 6 days 11 hours).
#11 Re: Dark Discussions at Cafe Infinity » Did you know? » 2019-05-19 10:17:59
#27. Did you know?
Renaud Capuçon is a French violinist, Ivan Fischer is a Hungarian conductor, and the Konzerthausorchester Berlin is a German orchestra.
#12 Re: Exercises » Adding 3 Numbers -- Easy Stuff » 2019-05-19 09:15:06
Do you have more interesting exercises than just adding three numbers?
#13 Re: Help Me ! » Sequence » 2019-05-19 02:39:03
It is clear that none of the terms in the sequence is divisible by 5. For
[list=*]
[*]
[/list]
Similarly none of the terms is divisible by 3, for
[list=*]
[*]
[/list]
It follows that
[list=*]
[*]
[/list]
i.e. consecutive terms are coprime; also
[list=*]
[*]
[/list]
i.e. alternate terms are coprime as well.
[list=*]
[*]
[/list]
Since a₁ = 1, k =1 fits the bill. And since the sequence is clearly strictly increasing, it is the only one that does.
#14 Dark Discussions at Cafe Infinity » Giving up smoking/drinking » 2019-05-19 00:02:00
- Alg Num Theory
- Replies: 2
Mark Twain is thought to have said something like the following:
Giving up smoking is the easiest thing in the world. I know because I’ve done it thousands of times.
Or words to that effect. Quote Investigator raises doubts about Twain’s authorship of the quote – but whoever actually first said it was right. I myself have found quitting tobacco/alcohol such an easy thing to do that I’ve been doing it for practically my whole life.
But this time I will stop for the last time. I finished smoking my last cigarette at exactly 01:00 BST (UTC midnight) and so, at the time of this post, it is 12 hours that I have quit tobacco-smoking.
As for quitting alcohol-drinking, I’ve had much more of a success with it. I last drank anything containing C₂H₅OH on New Year’s Eve – finishing it on the stroke of midnight GMT (UTC midnight): therefore, at the time of this post, I have been on the wagon continuously for 3 324 hours (138 days 12 hours, or 19 weeks 5 days 12 hours).
#15 Re: Dark Discussions at Cafe Infinity » Did you know? » 2019-05-18 23:38:58
#25. Did you know?
Yugarie (or eugarie), also called pipi, is “any of various shellfishes, esp[ecially] Plebidonax deltoides of Australia or Mesodesma novae-zelandiae of New Zealand” (Collins).
I learned this a moment ago when I was looking for a word beginning with y that had not already been used in the last-letter game I was playing.
#16 Re: Help Me ! » A linear algebra problem » 2019-05-18 23:04:48
#17 Re: Help Me ! » topology help » 2019-05-18 08:45:24
#18 Re: Help Me ! » inequality » 2019-05-18 07:10:54
Try Muirhead’s inequality and the fact that the sequence (4,0,0) majorizes (3,1,0) (i.e 4 ≥ 3, 4+0 ≥ 3+1, 4+0+0 ≥ 3+1+0).
#19 Re: Dark Discussions at Cafe Infinity » De- » 2019-05-18 03:37:12
The best way to fight depression is to be with people who shared good sense of humor.
Can you explain how this sentence is a humorous interpretation of depression?
I used to be in the codomain of a function, but I was deranged.
#20 Re: Help Me ! » abstract algebra » 2019-05-18 03:35:25
Let G be a group of order 595 = 5 × 7 × 17.
The number n of Sylow 17-subgroups divides 5 × 7 = 35 and is ≡ 1 (mod 17). Possibilities are 1 and 35.
Suppose 35. Then the intersection of all these subgroups (any two of which only have the identity in common since 17 is prime) would contain 1 + 35×(17−1) = 561 elements, i.e. 560 elements of order 17. Now, if P is a Sylow 17-subgroup and Q is a Sylow 5-subgroup, then PQ would be a subgroup of order |P||Q|/|P∩Q| = 85; moreover it would be cyclic, since P and Q are cyclic and their orders are coprime. But a cyclic subgroup of order 85 has φ(85) = 64 generators, i.e. 64 elements of order 85 – and we already have 560 elements of order 17.
Hence there can only be 1 Sylow 17-subgroup.
#21 Re: Dark Discussions at Cafe Infinity » Did you know? » 2019-05-18 01:04:36
#23. Did you know?
Sir Wilfrid Laurier was a Prime Minister of Canada (1896–1911), during whose term the country entered a period of prosperity known as the “Sunshine Years”.
I’ve just learnt this in the chapter on Prime Ministers of Canada in the section on people of the Reader’s Digest Book of Facts.
#22 Re: Dark Discussions at Cafe Infinity » De- » 2019-05-18 01:01:51
I used to be strong in a vacuum, but I was devoid of power.
#23 Re: Dark Discussions at Cafe Infinity » De- » 2019-05-17 22:20:37
I didn't want to leave the ship, but it was time for disembarkation.
One of the best methods of purification of water is distillation.
The machine was not in working condition, it was defunct.
Er, sorry, but I don’t think those are in line with the rules of the game.
The object of this game is not to make sentences using de-/dis- words, but to make humorous interpretations of such words. I don’t see anything humorous in those three sentences above. 
Look, I’ll explain. Take the opening examples by MathsIsFun:
Lawyers can get disbarred. So what about other jobs?
"I used to be an Electrician, but then I was de-lighted"
"I used to be a Guide, but then I was de-toured"
In the first sentence, “light” and “electrician” are related; in the second, “tour” and “guide” are related. Get it?
As for my own examples:
I was supposed to see my doctor today, but it was a disappointment.
When you see your doctor, you have an appointment with him/her. But my appointment was cancelled, so I called it a “disappointment”. Get it?
I wanted to be a flower, but it was a disaster.
An aster is a flower.
I used to be an entomologist, but I was debugged.
An entomologist studies insects; a bug is an insect. Get it now?
So, in this game, you don’t just make sentences. You choose a de-/dis- word, and make a sentence incorporating a humorous interpretation of it.
#24 Re: Dark Discussions at Cafe Infinity » De- » 2019-05-17 17:24:44
I used to be an entomologist, but I was debugged.