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#1 2013-05-01 14:01:54

limpfisch
Member
Registered: 2012-05-08
Posts: 11

help with group theory please.

let a,b be members of a group (G,*). Show that if (a*b) inverse = (a inverse)*(b inverse) then a*b = b*a

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#2 2013-05-01 19:10:18

Bob
Administrator
Registered: 2010-06-20
Posts: 10,053

Re: help with group theory please.

hi limpfisch

For simplification I'll leave out the * (say, multiply), use I for the identity and  -1 for an inverse

multiply both sides by ab

Now multiply both sides by ba

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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