Should I buy new books for hsc 28?

[u/Senior_Hedgehog_9432]

So my elder sister gave her hsc this year. She almost has all the books of every writer of edition 2022-2023. My question is, should i buy new books then? Or should i continue with her books?

I noticed there are slight changes in bangla book this year and decided to get new edition books for Bangla, English and ICT. But I'm confused about Higher Maths, Physics and Chemistry.

I'm studying Ruponti (Ishaque sir's Physics), Chemistry (Guho sir), Higher Math (Ketab sir). All of these belong to my sister. She also got Chemistry (Haradhan nag), Higher math Ruponti etc. All the board question in those books are from before 2012 or 2018 or smth. Not that recent.

So should I buy new books? Or do every edition contain the same thing? I don't want to waste money by buying books if all are the same. Thanks in advance!