Ordinal Arithmetic: $\omega\cdot \omega^{\omega}=\omega^{\omega}$

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Someone please can help me out ? Please. I am trying to use the definition of product ordinal and exponent ordinal.

Product ordinal: $\beta \cdot \alpha=\sup \{\beta \cdot \delta: \delta<\alpha\}$

Exponent ordinal: $\beta^\alpha=\sup \left\{\beta^\delta: \delta<\alpha\right\}$

can I define this one, in this way?

$\omega \cdot \omega^{\omega}=\sup\left\{\omega \cdot \omega^\alpha: \omega^\alpha<\omega^{\omega}\right\}.$

Is that possible?

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$\omega \cdot \omega^{\omega} = \omega^{1} \cdot \omega^{\omega} = \omega^{1+\omega} = \omega ^ {\omega}$

Note that for ordinals, $\alpha, \beta, \gamma$, it is true that $\alpha^{\beta} \cdot \alpha^{\gamma} = \alpha^{\beta + \gamma}$.