How can I calculate the supremum of the infimum of a function depending on two variables?
For example:
$$ \begin{align*} a =\sup_{t \geq 0} \left\{ \inf_{r \geq 0} \{ 10 \leq t + r \} \right\} \end{align*} $$
What I would have done is calculating the infimum first, only depending on r and then the supremum only depending on t.
This would give me $a = 10$. Is that correct?