Letφ:G→G′be a group homomorphism. Prove that Ker(φ) is a normal subgroup of G. Prove both that...

Letφ:G→G′be a group homomorphism. Prove that Ker(φ) is a normal subgroup of G. Prove both that it is a subgroup AND that it is normal.

Expert Solution

Colby Messinger answered 2 years ago

Prove that a subgroup H of a group G is normal if and only if gHg−1...

Prove that a subgroup H of a group G is normal if and only if gHg−1 =H for all g∈G

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