Outstanding. This man should have universities and cities and libraries named after him. Nonetheless, I would not give this book to a child. Its methods could greatly speed up the child but, until a person is sophisticated enough to understand what is going on behind the scenes and WHY these things work, learning to do math this way provides a weak foundation for learning higher concepts. This system's weakness is that it makes math seem like mystical powers. ( )

Trachtenberg was a Russian from what is now Ukraine (but for how much longer?) so
I have listed original language as Russian. It may have been German, French - anyone
know the truth? ( )

System designed to allow very fast multiplication of numbers by adding them in various combinations. Also addresses other operations. It's all real and I'm forever in debt to the teacher who had us doing a bit of it in school. Even if you aren't interested in taking time to learn the system, I think it's interesting to read about it. One has to wonder why it's not being taught in schools. I'll blame NCLB and move along to the next book. ( )

Indeholder "Forord", "Indledning: Hvad er Trachtenberg-systemet", "Vigtige udtryk", "1. kapitel", " Multiplikation med elleve", " Multiplikation med tolv", " Multiplikation med seks", " Multiplikation med syv", " Multiplikation med fem", " Multiplikation med otte og ni", " Multiplikation med fire", " Multiplikation med andre tal", "2. kapitel", " Hurtig multiplikation ved den direkte metode", " Multiplikander med 2 cifre", " Multiplikation af lange tal", " Nullerne foran multiplikanden", " Trecifrede multiplikatorer", " Mangecifrede multiplikatorer", " Resumé", " Tværsumsteknik", "3. kapitel", " Hurtig- eller 'tofinger'-metoden", " Ener-tier-systemet", " Multiplikation med éncifrede tal", " Multiplikation med tocifrede tal", " Multiplikation med mangecifrede tal med tocifrede multiplikatorer", " Trecifrede multiplikatorer", " Resumé", "4. kapitel", " Addition og det rigtige facit", " Kontrol af svaret", " Kontrolregning - almindelige metoder", " Tværsumsmetoden", " Tværsumsmetodens anvendelse", " 11-rest-metoden (11-prøven)", "5. kapitel", " Divition - Hurtighed og akkuratesse", " Den enkle divisionsmetode", " Den hurtige divisionsmetode", " Divisionsprocessen", " Metoden i detaljer", " Trecifrede divisorer", " Mangecifrede divisorer", " Restudregningen", " Kontrol af kvotient og rest", " Opgaver", "6. kapitel", " Kvadrat og kvadratrod", " Kvadrering af tocifrede tal", " Kvadrering af trecifrede tal", " Kvadratrod: Tre- og firecifrede tal", " Kvadratrod: Fem- og sekscifrede tal", " Øvelser", " Kvadratrod: Syv- og ottecifrede tal", " Kvadratrod: Længere tal", " Kontrol", "7. kapitel", " Aritmetrisk beskrivelse af metoderne i Trachtenberg-systemet", " Generelle tal", " 11-reglen", " Aritmetrisk manipulation", " Aritmetrisk bevis for Trachtenberg-systemet", " Multiplikation med seks", " Multiplikation med syv og fem", " Multiplikation med ni", " Multiplikation med otte", " Kvadrater", " Multiplikation efter tofingermetoden", " Encifrede multiplikatorer", " Flercifrede multiplikatore", " Tal af vilkårlig længde".

Bogen beskriver i alle detaljer et system som sætter en i stand til at regne ganske komplicerede regnstykker ud i hovedet og ganske hurtigt endda. Lommeregneren må siges at have gjort systemet inderligt overflødigt.
Ok bog i overflødigt system ( )

Can you multiply 5132437201 by 452736502785 in seventy seconds without reaching for your calculator? One young boy did, and got the right answer, by using the Trachtenberg Speed System of Basic Mathematics.
This revolutionary book was first published twenty years ago and became an instant, overwhelming bestseller. It has been reissued by public demand at a time when there is growing concern about the innumeracy of the young people going through school today.
The Trachtenberg method has been called the ""shorthand of mathematics"". It only requires the ability to count from one to eleven, does away with long division as we know it, and abolishes the multiplication table. Based on a series of simplified keys, it is easy to master and brings with it the benefits of greater speed, ease in handling numbers and increased accuracy. Mathematical computations take 80 percent less time to complete, and the system's rapid checking method ensures 99 percent accuracy.
At a time when conventional ideas about teaching methods are changing, the Trachtenberg System could well be the answer for the thousands of children who find mathematics difficult or simply boring. It could certainly change the lives of the innumerable adults who find the job of working out their accounts, checking a bank statement or totting up a shopping list a laborious and daunting task.