This is the first of four lectures we are showing from our 'Multivariable Calculus' 1st year course. In the lecture, which follows on from 'Introductory Calculus' which our students took in their first term, Sarah introduces the subject before going on to focus on Multiple Integrals in 2D. You can watch many other student lectures via our main Student Lectures playlist (also check out specific student lectures playlists):    • Oxford Mathematics Student Lectures -...   All first and second year lectures are followed by tutorials where students meet their tutor in pairs to go through the lecture and associated problem sheet and to talk and think more about the maths. Third and fourth year lectures are followed by classes.