is 2u content assessable in 3u? like series and sequences, loans, trapezoidal rule etc
yes and no? remember these are "EXTENSION" courses so they can be considered additions to the base "advanced math", if they want to, they can theoretically throw finance in MX2 under the "proofs topic" but highly unlikely. Generally, most of the content unique to MX1/2 is in the paper and the general rule is that as long as the question has some link to a syllabus point, its fair game, e.g volumes q in hsc 2021 -> link to MX2 integration techniques.
i wouldnt necessarily say all of 2u is gonna be in 3u but i wouldnt be surprised to see 2u content with extra layers in 3u. Honestly just revise 2u off notes and ull be fine, as long as u get the jist of it. The main part is ur 3u content.
correct me if im wrong, this was my thought process/experience in the hsc im abt to finish 1st year uni