#### quasar987

Science Advisor

Homework Helper

Gold Member

- 4,771

- 5

Hi people.

In the proof of theorem 2B.1 page 169-170 of Hatcher (generalized Jordan curve theorem), item (b) is proved by induction on k and the case k=0 is handled by noticing that S^n - h(S^0) is homeomorphic to S^(n-1) x

In the proof of theorem 2B.1 page 169-170 of Hatcher (generalized Jordan curve theorem), item (b) is proved by induction on k and the case k=0 is handled by noticing that S^n - h(S^0) is homeomorphic to S^(n-1) x

**R**. How does he know that [tex]\widetilde{H}_i(\mathbb{S}^{n-1} \times \mathbb{R})[/tex] is**Z**if i=n-1 and 0 otherwise?
Last edited: