You Don't Cast Spells By the Rules, Do You?

This is an iron chain forged from mana.

    You cannot break free using brute force.

    But no problem, you're a wizard too. You try to defeat magic with magic.

    But you failed. You have to re-examine the chain and discover that it is composed of individual letters emitting a faint glow, connected by many symbols that you recognize when taken alone but become completely incomprehensible when put together, ultimately forming a series of inequalities.

    Your intuition tells you that the key to breaking the magical shackles is solving these inequalities.

    But the problem is......

[if......f(x)≥1/4,f(2)≥0,x≥3...max{f(x)}=?]

"???"

"Who the hell uses magic like this??