bang (one's) head against a wall

To attempt continuously and fruitlessly to accomplish some task or achieve some goal that is or seems ultimately hopeless. I feel like I've been banging my head against a wall trying to understand this math equation. Some people are never going to agree with you on this, so it's no use banging your head against a wall trying to convince everyone.

Common Names:

Name	Pronounced	Usage
ViỆN	-	Vietnamese
Menelaus	-	Greek Mythology (Latinized)
Emi	e-mee	Japanese
Sanchia	-	Spanish
ÁSketill	-	Ancient Scandinavian
Raheem	rah-HEE:M	Arabic