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A manifold $M^n$ is called parallelizable if and only if there exist n vector fields on $M^n$ which are independent at each point of $M^n$. Could you help me figure out the vector fields for $S^n \times R$?

Yeezus
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    Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level. – Fly by Night Nov 08 '17 at 22:00

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Consider $f:S^n\times \mathbb{R}\rightarrow \mathbb{R}^{n+1}-\{0\}$ defined by $f(x,t)=e^tx$, it is a diffeomorphism where you identify $S^n $ with the unit sphere of $\mathbb{R}^{n+1}-\{0\}$; $\mathbb{R}^{n+1}-\{0\}$ is parallelizable since it is an open subset of $\mathbb{R}^{n+1}$.

Tsemo Aristide
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