Exact Differential Equations: Test, Potential Function, and Integrating Factors

Learn how to recognize and solve exact differential equations using the exactness test M_y = N_x, recover a potential function F(x,y), apply initial conditions, verify implicit solutions, and use special integrating factors when an equation is not exact. This rigorous visual lesson also explains domain restrictions, conservative vector fields, line integrals, and the punctured-domain caveat.

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Stokes’ Theorem Explained: Why the Edge Knows the Surface

Stokes’ Theorem says that boundary circulation equals the total curl through a surface. In this Woody Calculus visual lesson, learn how Stokes’ Theorem connects line integrals, surface integrals, curl, orientation, the right-hand rule, Green’s Theorem, and vector calculus in Calculus 3.

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Green’s Theorem Explained: Why a Boundary Knows Everything Inside

Green’s Theorem turns a boundary line integral into an interior double integral. In this Woody Calculus visual lesson, learn how Green’s Theorem connects circulation, curl, flux, area, line integrals, double integrals, Stokes’ Theorem, and the Divergence Theorem in Calculus 3.

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Line Integrals and Vector Fields: What They Measure in Calculus 3

Line integrals are one of the core ideas in Calculus 3 and vector calculus. Learn what line integrals measure, how vector fields interact with paths, why direction matters, and when different paths from the same start to the same end can produce different work.

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