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

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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**bob bundy****Administrator**- Registered: 2010-06-20
- Posts: 8,462

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

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Sometimes I deliberately make mistakes, just to test you! …………….Bob Bundy

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