There are four sets of advanced mathematics, one of which is the most difficult, and the others are decreasing in turn. Compared with Math III, Math I is much more difficult than Math III in the depth and breadth of content. Compare the contents of these two books carefully. You will find that some contents of math 1 are not available in math 3. Judging from the depth of the problem, the rarity of mathematics one will obviously be even greater. Generally, only students of science and engineering will take Math I, while Math III is generally a liberal arts exam.