0.
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homomorphism maps identity to identity
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1.
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0. and
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. |
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2. Choose where |
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- 3.
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2.
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- 4.
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k is in G and eG is identity of G(usage3)
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.
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5.
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2, 3, and 4.
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6. is identity of
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definition of identity(usage 4)
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0. Choose |
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- 1.
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0.
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- 2.
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definition of inverse in G (usage 3)
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- 3.
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homomorphism maps inverse to inverse
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- 4. k has inverse k-1 in ker f
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2, 3, and eG is identity of ker f
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5. Every element of ker f has an inverse.
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0. Choose |
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- 1.
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0.
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- 2.
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f is a homomorphism
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- 3.
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1. and eK is identity of K
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- 4.
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0. ker f is a subset of G |
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1. is associative in G |
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2. is associative in ker f |
1 and 2
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