Exercise 5.
Consider the following two graphs:
- \(G_1\)
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\(V_1=\{a,b,c,d,e,f,g\}\)
\(E_1=\{\{a,b\},\{a,d\},\{b,c\},\{b,d\},\{b,e\},\{b,f\},\{c,g\},\{d,e\}\text{,}\)
\(\{e,f\},\{f,g\}\}\text{.}\)
- \(G_2\)
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\(V_2=\{v_1,v_2,v_3,v_4,v_5,v_6,v_7\}\text{,}\)
\(E_2=\{\{v_1,v_4\},\{v_1,v_5\},\{v_1,v_7\},\{v_2,v_3\},\{v_2,v_6\}\text{,}\)
\(\{v_3,v_5\},\{v_3,v_7\},\{v_4,v_5\},\{v_5,v_6\},\{v_5,v_7\}\}\)
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Let \(f:G_1 \rightarrow G_2\) be a function that takes the vertices of Graph 1 to vertices of Graph 2. The function is given by the following table:
\(x\) \(a\) \(b\) \(c\) \(d\) \(e\) \(f\) \(g\) \(f(x)\) \(v_4\) \(v_5\) \(v_1\) \(v_6\) \(v_2\) \(v_3\) \(v_7\) Does \(f\) define an isomorphism between Graph 1 and Graph 2?
Define a new function \(g\) (with \(g \ne f\)) that defines an isomorphism between Graph 1 and Graph 2.
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Is the graph pictured below isomorphic to Graph 1 and Graph 2? Explain.