Applied mathematics consisted principally of Applied Analysis, most notably differential equations; Approximation Theory (broadly construed, to include representations, asymptotic methods, variational methods, and numerical analysis); and Applied Probability. These areas of mathematics were intimately tied to the development of Newtonian physics, and in fact the distinction between mathematicians and physicists was not sharply drawn before the mid-19th century. In the early 20th century subjects such as Classical Mechanics were often taught in applied mathematics departments at American universities rather than in physics departments, and Fluid Mechanics may still be taught in applied mathematics departments. Engineering and computer science departments have traditionally made use of applied mathematics.
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