In the set theory if A= {A, B} and B= {A, C} does B contain itself?

The expression [math]A=\{A,B\}[/math] is meaningless. It does not define a set [math]A[/math], nor anything else. (EDIT: some people commented that [math]A=\{A,B\}[/math] may be meaningful in v…

Top stories for Long   In the set theory if A= {A, B} and B= {A, C} does B contain itself? Alon Amit, PhD in Mathematics; Mathcircler. • Answered February 4, 2018 The expression [math]A=\{A,B\}[/math] is meaningless. It does not define a set [math]A[/math], nor anything else. (EDIT: some people commented that [math]A=\{A,B\}[/math] may be meaningful in various alternative systems of... Read more » 159 25   Why is sobriety so extremely boring? Christopher Blake, Been traveling or moved around since 5 • Answered October 16 Soooooooooo I am on my second month and I am bored and depressed, and like many have said, the reality of my damaged and lonely life is now visible and obvious. Truthfully,... Read more » 180 77   How can we live in peace while there are atheists? Asked in Divine Atheists • Answered by Try to use Facts, not Hearsay. • Mon Interesting, The Bible is full of text about violence, Murder, Rape, Genocide, War, punishment, The Qur'an is full of text about violence, Murder, Rape, Genocide, War, punish... Read more » 106 114   Why do so many scientists dislike the German theoretical physicist Sabine Hossenfelder? David Kahana, worked at University of Regensburg • Answered September 29 Sabine Hossenfelder was a post-doctoral worker or a graduate student, I'm not quite sure which, at what became Walter Greiner's Institut at the Goethe University, in Frankf... Read more » 931 147   How does sepsis feel? Deborah Jugan, former Attorney • Answered November 4 For me, I felt OK but could not shake the feeling I had something wrong with me. The next day I went to the dentist for a regular appt. but that feeling I had now felt like... Read more » 988 53   How can you prove that √6-√2 > 1 without estimating √6 or √2? Enrico Gregorio, Associate professor in Algebra • Answered March 12, 2023 No estimate necessary. I like to use ? in order to denote a comparison symbol that may be [math]<[/math] or [math]>,[/math] to be determined using only "reversible" steps: [math]\begin{array}{ll} \sqrt{6}-\sqrt{2}\mathrel{?}1 & \text{move the negative term to the right-hand side} \\ \sqrt{6}\mathrel{?}1+\sqrt{2} & \text{square} \\ 6\mathrel{?}1+2\sqrt{2}+2 & \text{leave the radical alone} \\ 3\mathrel{?}2\sqrt{2} & \text{square} \\ 9 \mathrel{?} 8 \end{array}[/math] Now we know that the inequalit... Read more » 162 24   Alberta will soon secede and become the 51st state once Bill 54 passes and a referendum is held (it will pass). Will they be considered a Midwestern or Western state? JoelleEmmily, Researcher (Nuclear Energy, Economics) at Freelancing (1992-present) • Updated November 13 Q: Alberta will soon secede and become the 51st state once Bill 54 passes and a referendum is held (it will pass). Will they be considered a Midwestern or Western state? A: ... Read more » 3.3K 430   Was Mister Rogers ever implicated in any type of scandal? Jean-Marie Valheur, knows a bit about a bit • Answered October 15 Fred Rogers was a great guy, but also a guy born in 1928. He was a religious man, and while open-minded, he knew the power of keeping up appearances. When the actor François... Read more » 5.3K 557   How much fecal matter is held in the human body? Websites like Google are claiming 10-25 pounds, but it seems to be suspected commercial sites that I don't trust. Mike Condron, M.D. Medicine, Meharry Medical College (2004) • Updated March 12, 2018 I handle colons quite a lot in my work (I am a forensic pathologist and have performed over 1600 autopsies). I did a study once of the utility of opening colons to look for... Read more » 20.4K 1.1K   It's almost 2026. Would you choose a Mac or a Windows machine? Franklin Veaux, Technology enthusiast, mad engineer, and tech startup founder. • Answered November 5 As we come to the end of 2025, I think buying a new Windows machine is something of a perverse act of idiocy. The Windows 11 Terms of Use for Windows 11 25H2 specifically gr... Read more » 1.9K 215   I cheated 10 years ago and my spouse doesn't know. Do I have to tell him? Asked in Affairs: The "Other Woman" /The "Other Man" Space • Answered by Richard J. Head • November 8 I have been a lawyer since 1983, and have been handling divorces for 40 years. My law practice has taught me that people disclose past infidelity for three reasons: 1) They... Read more » 4K 536   Why do liberals not want to hear a Republican's point of view? Linda vanDyck, former World traveler, Stewardess, CPA • Updated October 30 I married a Republican. He was a member of the Young Republicans of Philadelphia and had just earned a PhD in Physics from the University of Pennsylvania. I had a high scho... Read more » 8.9K 1.6K Read more in your feed

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My Honda Accord has 415,000 miles on it. People keep telling me to contact Honda corp...?

My son has a 2001 Nissan Xterra with around 380,000 miles on it. He approached Nissan about receiving some benefit from it lasting that many miles. Their response was along the lines of "That's …

Top stories for Long   My Honda Accord has 415,000 miles on it. People keep telling me to contact Honda corporate and tell them because they might give me a really good deal on a newer model. Is there any truth to this? Mel Robinson • Answered October 27 My son has a 2001 Nissan Xterra with around 380,000 miles on it. He approached Nissan about receiving some benefit from it lasting that many miles. Their response was along... Read more » 1K 247   Why do pilots say, "Roger"? What does Roger mean in aviation? Ken Spencer, Private pilot, single engine land and sea, and instrument • Answered February 22, 2024 The terms "Roger" and "Wilco" are not longer used in modern aviation phraseology. If the tower clears me to land, I repeat the phrase "Cleared to land runway 24." What's go... Read more » 2.4K 259   How is the life of a male without marriage? Asked in Stuff Men Have To Deal With • Answered by OmCream IceCream • October 26 I am 42 years old. Single and never married. Here is how my life is as a guy's life without marriage.. Simplicity I was living and working in US. I came to a point where I di... Read more » 1.9K 350   Diaz Gabriela, Reseracher at Academic Research (2004-present) • Posted Jan 29 In 1947, a woman walked into a grocery store in Memphis, Tennessee, to drop off a roll of film to be developed. As she entered, she realized she had one last photo left to take. She saw a boy outsid... Read more » 2.6K 104   Why do people take their leftovers home when they go out to eat at restaurants? Srinath Nalluri, M.Sc, B. Eng Mechanical Engineering & Minor, National University of Singapore (2... • Answered September 21, 2023 I worked in a restaurant part-time during my college. On an average day, the restaurant would be mildly busy. Cooking, serving, clearing and cleaning will happen simultaneous... Read more » 2.7K 279   I'm peeing dark brown, basically looking like coffee. I think it's my kidneys. Are there any other symptoms my liver or kidneys do when they are shutting down? Thomas Cayne, Writer, painter, thinker, madman. • Answered September 20 My girlfriend once had a patient who happened to a pee a dark, brownish and stinking liquid, which appeared to contain feces after further examination. It turned out that th... Read more » 1.3K 214   How did Anthony Hopkins quit drinking alcohol? Jean-Marie Valheur, we're all actors, in a sense • Answered October 26 Anthony Hopkins has been sober for 50 years. Before that, he was a heavy drinker. In a recent interview, he described the moment he decided never to drink again — it was aft... Read more » 816 25   What is the most obvious theorem in mathematics? Brian Bi, uses math • Answered May 20, 2015 Surprised nobody has yet mentioned Tarski's deduction theorem, which is so "obvious" that every math student has used it implicitly without even realizing that it needs to ... Read more » 635 24   Antarctica has been building massive ice, the polar bear population has grown yearly for a decade, and the ozone hole has been shrinking for 12 years. Doesn't that prove global warning is BS? Colin Sanders • Answered October 30 No, Linda Anthis, what that proves is that you speak before you understand anything and demonstrate that it would have been better to not say anything. Antarctica has been g... Read more » 821 117   Warren Grant • Posted Oct 6 About a year ago, my wife and I stopped by Waffle House to eat. When we went to pay the bill, for some reason we were scrounging for money to pay. Then I candidly said it looks like we are going to... Read more » 7.7K 292   If Tony Stark died while inside his Iron man suit, how will the suit respond? Asked in MarvelHolics • Answered by Matt Ferreira • July 8 We saw this in Endgame. After Tony made his sacrifice with the snap he was borderline unresponsive. When Pepper asked F.R.I.D.A.Y. about his status and she replied "life fu... Read more » 1.5K 68   Why is soldering not allowed (or common) for home wiring? Michael Mark Ross, I'm an eclectic and iconoclastic information technologist • Answered June 12, 2018 These things changed everything - twist-on plastic connectors: They were not widely used until the 1970s in the U.S. Until then, homeowners, at least, would just twist wires... Read more » 930 167 Read more in your feed

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