Some help for solvers of Nation puzzle #3233.
Hints for all solvers:
9A: You may not be familiar with this mathematician. (Moreover, if you are, you may not know the correct pronunciation of his name.)
15A: The clue might be difficult to parse. The definition is “a starter.”
25A: You may not have come across this meaning of “cashier.” The definition is “Truce.”
1D: The clue depends on a possibly unfamiliar meaning of “proper.”
3D: Another less-than-well-known word. The definition is “glasses.”
Hints for beginners:
17A: A synonym of “change,” dropping the last letter, is written backwards inside a word for “bank employee.”
19A: “Resistance” is abbreviated to R in physics.
2D: is a reversed hidden word.
8D: The definition is “dislike.”
22D: This is a hidden-word clue.