10-17-2003, 12:29 AM
I too have read a bit of Trachtenberg Speed System for basic mathematics and if I recall correctly the author wrote it while in jail. In the appendix he gives mathematical proofs (distributive law, etc. IIRC) of the techniques he used.
I bought it for a few rupees from a footpath hawker in Connaught Place in Delhi, but the amazon page linked to above shows a different cover and a price of $68.95. Amazing!
I bought it for a few rupees from a footpath hawker in Connaught Place in Delhi, but the amazon page linked to above shows a different cover and a price of $68.95. Amazing!