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.