Betti numbers of 3-manifolds (Ex)

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Revision as of 08:38, 6 January 2019

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\newcommand{\sp}{^}G$ be the fundamental group of a closed orientable $3$$3$-manifold. Show that $b_2(G) \le b_1(G)$$b_2(G) \le b_1(G)$. 

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