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Stu Savory ;-) School report for Stu Savory
Eunoia, who is a grumpy, overeducated, facetious, multilingual ex-pat Scot, blatantly opinionated, old (1944-vintage), amateur cryptologist, computer consultant, atheist, flying instructor, bulldog-lover, Beetle-driver, textbook-writer, long-distance biker, geocacher and blogger living in the foothills south of the northern German plains. Not too shy to reveal his true name or even whereabouts, he blogs his opinions, and humour and rants irregularly. Stubbornly he clings to his beliefs, e.g. that Faith does not give answers, it only prevents you doing any goddamn questioning. You are as atheist as he is. When you understand why you don't believe in all the other gods, you will know why he does not believe in yours.

Oh, and after the death of his old dog, Kosmo, he also has a new bulldog puppy, Clara, since September 2018 :-)

Some of my bikes

My Crypto Pages

My Maths Pages

Monday, January 18, 2021

Laws of Nature 2.0

Old friend Derek (Canada) sent these revised laws of nature, so I'm blogging them during my down time. All credit to Derek pls.

  • Law of Mechanical Repair - After your hands become coated with grease, your nose will begin to itch and you'll have to pee
  • Law of Gravity - Any tool, nut, bolt, screw, when dropped, will roll to the least accessible corner.
  • Law of Probability - The probability of being watched is directly proportional to the stupidity of your act.
  • Law of Random Numbers - If you dial a wrong number, you never get a busy signal and someone always answers.
  • Supermarket Law - As soon as you get in the smallest line, the cashier will have to call for help.
  • Variation Law -If you change lines (or traffic lanes), the one you were in will always move faster than the one you are in now.
  • Law of the Bath - When the body is fully immersed in water, the telephone rings.
  • Law of Close Encounters - The probability of meeting someone you know increases dramatically when you are with someone you don't want to be seen with.
  • Law of the Result - When you try to prove to someone that a machine won't work, it will.
  • Law of Biomechanics - The severity of the itch is inversely proportional to the reach.
  • Law of the Theatre & Hockey Arena - At any event, the people whose seats are furthest from the aisle, always arrive last. They are the ones who will leave their seats several times to go for food, beer, or the toilet and who leave early before the end of the performance or the game is over. The folks in the aisle seats come early, never move once, have long gangly legs or big bellies and stay to the bitter end of the performance. The aisle people also are very surly folk.
  • The Coffee Law - As soon as you sit down to a cup of hot coffee, your boss will ask you to do something which will last until the coffee is cold.
  • Murphy's Law of Lockers - If there are only 2 people in a locker room, they will have adjacent lockers.
  • Law of Physical Surfaces - The chances of an open-faced jam sandwich landing face down on a floor, are directly correlated to the newness and cost of the carpet or rug.
  • Law of Logical Argument - Anything is possible if you don't know what you are talking about.
  • Brown's Law of Physical Appearance - If the clothes fit, they're ugly.
  • Oliver's Law of Public Speaking - A closed mouth gathers no feet.
  • Wilson's Law of Commercial Marketing Strategy - As soon as you find a product that you really like, they will stop making it.
  • Doctors' Law - If you don't feel well, make an appointment to go to the doctor, by the time you get there you'll feel better... But don't make an appointment, and you'll stay sick. This has been proven over and over with taking children to the pediatrician.

Comments (1)
John (USA) wrote "Please tell Derek that his list is wonderful! Thanks for sharing!" Wilco.

Friday, January 8, 2021

Thank you Georgia

Thank you Georgia, for choosing both Democrat senators. Now we can expect a bit more peace and quiet; Biden/Harris can push their agenda through without obstruction from Moscow Mitch :-)

Just 12 more days until you can lock Trump up, USA :-) Way to go!

Comments (3)
Doug (Canada) sent this joke : " A teacher goes around her class asking each of the kids what they need at home. Joey says, "A computer." The teacher replies, "That would be very useful." Jenny says, "A new lawn mower." The teacher again replies, "That would also be very useful." Little Johnny pops up and says, "At my house we don't need anything!" The teacher asks him to think again carefully, as "everybody needs something." Little Johnny replies, "No I'm sure we don't. When Trump was elected, I clearly remember my dad saying, 'Well, that's the last fucking thing we needed!" " Very good, Doug. I always like Little Johnny jokes :-) Thanks :-)
David (NY,NY) asks "What do you think of the storming of the Bastille Capitol, D.C.?" Personally? Maybe I'm paranoid, but I think tRump is devious enough to have hoped for a blood bath - sacrificing his tRumpanzee mob of useful idiots - so that he could declare martial law and thus remain pResident! Sly, cheating bastard that he is! That's why he waited before sending in the National Guard, but only a few died, not enough to warrant martial law. He wanted hundreds or thousands dead, just to get his way!
Billions of Versions... wrote " That last day will become the new "Longest day" taking over from D-DAY." Lock him up!

Sunday, January 3, 2021

Solving quadratic equations another way

My short-term memory is worsening, so I'm kicking off 2021 with an anecdote from my long-ago schooldays instead.

Back in secondary school we had a good maths teacher, Jeb, but who insisted we do things HIS way. I didn't like that. And thereby hangs this tale.

Once, he was teaching us how to solve quadratic equations (see the equation on the left, below). Quadratic equations have at most two roots (since this is the highest power of x in the equation). So we had to learn by rote how to calculate these roots; see the equation on the right below.

Remember, this was back in the days before calculators; calculations were either done in your head or with pencil and paper. This usually took the class 5 or 10 minutes; but I knew a faster way, using the irrationality theorem :-)

Suppose he wrote as the problem to be solved 4x2 - 32x + 60 =0. In order to use the irrationality theorem, we need a=1 not 4, so I divided his problem by 4 getting x2 - 8x + 15 =0. Now the irrationality theorem tells us that the roots of the problem are either whole number factors of c (here 15), or are irrational. Irrational means the number cannot be written as a ratio; so something like root(2) instead. Since this is only a simple secondary school problem, I reasoned that Jeb wouldn't give us a problem with irrational roots.

So the roots had to be 1,3,5 or 15 (all the factors of c). Plugging each of these in turn mentally into x2 - 8x + 15 =0 gave me the roots as 3 and 5. All this mentally in less than a second. So I could blurt out "3 and 5" before Jeb had even finished chalking the "=0" onto the blackboard :-) Job done before he'd finished or the rest of the class had even started :-)

Results : class thought I was some kind of mental giant for using the equation on the right so fast. But only an A- from Jeb for the right answer but not using his method; most unfair I thought. Not to say irrational ;-)

Jeb wanted me to show my working, so I wrote a cubic equation on the board x3 - 7x + 6 =0. By the same reasoning, the roots can only be 1, 2, and 3. And since these are the 3 roots, there can be no irrational roots. And Jeb's equation (on the right) doesn't work for cubic equations, so my method was more general I claimed.

What an obnoxious little know-it-all I was and still am ;-)

Comments (1)
Anon (UK) wrote "Here's Jeb's marking for you."

Link to the previous month's blog.
Recent Writings
Laws of Nature 2.0
Thank you Georgia
Quadratic equations
Give generously ?
Dead Stick Landing
Salmon Pie
Local call from ET ?
My last Great Conjunction
Murder-Witness ? Alexa!
Roast me!
French is not always...
Not always 5 & 5 digits
No More Fucking :-(
Local Lockdown Library
Extreme Hotels
The Sound of Silence
Guten Morgan!
Unlucky for some :-(
Biden Harris anagrams
Flying the Shuttle Carrier
NOT about the US election
End of Days?
Where's the Mass?
A different Halloween

Ain Bulldog Blog
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Billions of Versions...
Cop Car
Digby's Hullabaloo
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Fail Blog
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Greg Laden
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Observing Hermann
Scotties Toybox
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Starts with a Bang
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FWIW, 153 is a triangular number, meaning that you can arrange 153 items into an equilateral triangle (with 17 items on a side). It is also one of the six known truncated triangular numbers, because 1 and 15 are triangular numbers as well. It is a hexagonal number, meaning that you can distribute 153 points evenly at the corners and along the sides of a hexagon. It is the smallest 3-narcissistic number. This means it?s the sum of the cubes of its digits. It is the sum of the first five positive factorials. Yup, this is a 153-type blog. QED ;-)
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