Let G be a topological group and $H\le G$.
Let $\pi: G\to G/H$ be the canonical projection and a continuous $\sigma: G/H\to G$ such that $\pi \circ \sigma = Id$.
Prove that G is homeomorphic to $G/H\times H$.
I am confused by this question because $\pi$ is a bijective morphism so we should rather have $G\cong G/H$.
Thank you for your help.
Edit
Thanks to your comments/answers I cleared my confusion. Now if I go back to the original question. Wy is $G$ homeomorphic to $H\times G/H$.
Factorization theorem gives an isomorphism $G\cong H\times G/H$ because $H=\ker \pi$ and $G/H=\text{Image}(\pi)$.
I don't see how to build this homeomorphism by hand.
Thanks again.
If we take $H=\mathbb{Z}$ in $G=(\mathbb{R},+)$ then $G/{H} \simeq S^1$, the unit circle, and $\mathbb{R} \not \simeq S^1 \times \mathbb{Z}$, for connectedness reasons alone...
As to your question with a continuous section, this paper looks relevant (though it's only for Abelian topological groups).