Set theory - Minimum Principle

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I would really appreciate your help with the following question,

Let us define a Preorder T over ${\mathbb R^\mathbb{R}}$ :

  • ${ f T g \iff \exists h \in \mathbb R^\mathbb{R}(h \circ g = f)}$

Let ${E = T \cap T^{-1}}$ be an equivalence relation ,

we will define a new relation $T'$ over ${ \mathbb R^\mathbb{R}/E}$ :

  • ${[f]_E T' [g]_E\iff fTg }$

we will assume that $T'$ is a partially ordered set and that it is well defined,

prove that there exist Minimum and Maximum in ${<\mathbb R^\mathbb{R}, T'>}$


I started with induction and proved that $[m]_E$ is Min in ${<\mathbb R^\mathbb{R}}$ \ ${\{[a]_E\}, T''>}$

${T'' = \{<x,y> \in T'| x,y \in \mathbb R^\mathbb{R}}$ \ ${\{[a]_E}\}\}$

But got stuck proving that ${<[m]_E,[a]_E>\in T'}$

Thanks in advance!