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Differential Equations
The Geometric View of ODEs
01Direction Fields and the Geometric View of ODEs02Integral Curves and the Isocline Method03Perpendicular Isoclines: The Circles of y' = -x/y04Isocline Corridors and a Trap for Solutions05Existence and Uniqueness: One Curve Through a Point06Where Existence and Uniqueness FailProblem set0/10Problem set 20/10MIT problem set0/3Practice∞
Numerical Methods
01Euler's Method and Its Three Equations02Euler's Method by Hand: Building the Table03Convexity and the Sign of Euler's Error04First Order Error: Halve the Step, Halve the Error05Improved Euler (RK2): Averaging Two Slopes06Runge-Kutta 4 and the Price of Accuracy07Singular Points: Where Every Method FailsProblem set0/10Problem set 20/10MIT problem set0/1Practice∞
First-Order Linear Equations
01First Order Linear: Standard Form and the Sign of p02The Conduction-Diffusion Model: Newton's Law of Cooling03The Integrating Factor and the Four-Step Method04Integrating Factors: Two Mistakes and a Trick Question05Constant Coefficients: Steady State and TransientProblem set0/10Problem set 20/10MIT problem set0/1Practice∞

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