Dear Calculator friends, After my friends Andy, Gert and Jan went home, I found this "explanation" of the chinese remainder theorem, which to me is indeed...
Hi Willem! Ok, Simulateous congruencies are something you do know - a "congruence" is a modulo. So if I ask what is the remainder when 67 is divded by 12, I...
Hi Andy, Your reaction is printed and will be studied. I do not know where the CRT is used for, anyhow in the case of the remainder division it was crystal...
Dear Mr. Manchali, As I am not very sure if my message enters in your mailbox I make a cpy for Mental Calculation. Of course I am minterested if my anwer meets...
Hi folks, It's been a while since I posted anything to the group, so I thought I'd out something down on this subject. Willem's '11 test' is very much akin...
Hello fellow calculators, Would anyone be kind enough to in detail (step by step) show how to calculate the square root of this mentally as my algorithm...
Dear Josh, Of course you get help! Ok sqrt 100044. a.. the nearest square under your number is 316²= 99856. b.. Subtract this of 100044= 188 c.. 188/2=94÷ =...
Dear Willem Bouman, This is the most important response I have ever recieved for I finally understand the method and the logic behind it. I am hooked and have...
Hello everyone, re: 188/2=94÷ = 2 r 32, as we later on make further subtractions 3r1 would bring us in trouble Is there a 'for dummies' version of this...
Hi Josh, Willem, and... well, everyone really. The number 100,044 gives quite a good example of a technique I sometimes use to find square roots. Willem's...
... Hi Mike, This method was presented in my book back in 1993, though performed two digits at a time rather than one digit at a time. I have an online ...
Dear Mr. Josh, For decimal cubic roots I have no algorithm with the same rate of accuracy. If there is one, I am, as usual very interested. Regards, willem...
Dear Mr. Mike, It took me some time, now I see: I omitted 31, so it has to be: 188/2=94÷31= 2 r 32. Ok now? Regards, willem Bouman ... Van: Michael Curtis ...
Hello Ron, Back when I decided to seriously look into mental math, I bought a few books (yours being one of them). I never commoitted the time, I am afraid. I...
Dear Willem,How is your method to find the nearest square? in the exampe 316^2. I supose there are a lot of ways to calculate it but i dont know which is the...
Dear Michael, Owing to my good memory I know the squares till 1.000 by heart since my 14th anniversary. With algebra we studied square roots. I knew already by...
Dear calculator friends, Please give a reaction on this: Deep roots We did decimal root of 100044 and saw there were no rounding problems. We'll meet these...
Hello there folks, it's me again. The root of a specified number, taken to a specified depth and required to a specified level of accuracy, can only ever...
Good morning George, Thanks for your reaction. It is printed and will be thoroughly studied. Kindest regards, Willem Bouman ... Van: George Lane Aan:...
Good afternoon George, The morning gave me the possibility to think after your reaction, again thanks! I Think my problem lies somewhere else, square roots...
Hi Willem, and all the rest of you too, of course. The idea of the square root as I have used here was simply an illustration of the necessity of using...
... How fast can you do 8 digit and five digit multiplications,? How do you remember the cariies and how do you get them correctly if i get like 55 seconds on...
Dear calculator friends, My question is it, how I can work out trigonometric problems like sine, cosine and tangent(easily???) in my head. Are there any tricks...
Judging by your examples your arguments are in degrees in which case I would simply memorise the relevant tables up to all the functions you have mentioned are...
Hi Mario! These are very tricky, but not impossible. Do you have a good mathematical knowledge? The Sines, Cosines and tangents of 0,30,45,60 and 90 are all...
Hi folks, I'm back - just like the proverbial bad penny. However, I hope I can be a bit more useful than a duff coin! I've been working on a system for...
WHOOOPS!! It seems only a part of my message got through to you the other day. Unfortunately, I have parted company with the original - please bear with me...
Hi folks, I'm back - just like the proverbial bad penny. However, I hope I can be a bit more useful than a duff coin! I've been working on a system for...
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