The second test of mathematics is proper subset of number one, but he doesn't take probability theory, series, triple integral, curve integral and surface integral (most engineering majors take the second test of mathematics, and there are also special majors: materials, textiles, agricultural engineering, industrial engineering, forestry engineering, food and other masters and masters also take the second test of mathematics).
The third test of mathematics is high number, linear algebra and probability theory, without triple integral, curve integral and surface integral. The third test of mathematics has separate contents: difference equation, mathematics I and mathematics II do not test this knowledge point. (Economics, Management and Mathematics III)
Majors who may take Math I and Math III: Management Science and Engineering.
In terms of difficulty, Math 1 ≥ Math 2 >: Math 3.