In D4, let K = {R0, D} and let L = {R0, D, D ', R180}.
Chapter 9, Problem 55E(choose chapter or problem)
In D4, let K = {R0, D} and let L = {R0, D, D ', R180}. Show that but that K is not normal in D4. (Normality is not transitive. Compare Exercise 4, Supplementary Exercises for Chapters 5–8.)
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