Non-explicit use of Weirestrass Extreme Value Theorem

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Consider the following well known theorems due to Weierstrass. If $f:[a,b]\to\mathbb{R}$ is continuous on its domain, then

  1. $f$ is bounded from above and from below.
  2. $f$ attains its maximum and minimum on the interval, i.e. - There exists $x_{\min},x_{\max}\in[a,b]$ such that for all $x\in [a,b]$ one has that $$ f(x_{\min} ) \leq f(x) \leq f(x_{\max}) \, .$$

My Question: Most of the examples I've seen for using these theorems are very explicit - show that the function $f$ under some conditions has maximum/minmum. I'm looking for an example in which we need to use either of these theorems, but we are not asked to do it explicitly.

In terms of prerequisites I can only rely on these theorems, basic continuity definitions and the mean value theorem.

Thanks