Answer to Question #351024 in Abstract Algebra for Fed

Abstract Algebra

Question #351024

3.5 If U is an ideal of R and 1 ∈ U, prove that U = R.

Expert's answer

Since for any "r\\in R" and "u\\in U", "ru\\in U" we have for any "r\\in R", "r\\cdot 1=r\\in U". Hence "R=U".

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