You don't cast spells by the rules at all, do you?

This is an iron chain made of magic power.
You can't break free by brute force.
But it doesn’t matter, you are also a wizard, and you try to defeat magic with magic.
But you failed. You had to re-examine the chain and found that it was made up of letters that glowed one by one, linked by many symbols that you could recognize individually but could not understand when put together, and finally formed inequalities.
Your intuition tells you that the key to breaking the magic shackles is to solve these inequalities.
But the problem is...
【if……f（x）≥1/4，f（2）≥0，x≥3…max{f（x)}=?】
"???"
"Whose magic is used like this?"