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Gilbert Strang, Calculus, 3rd edition (Wellesley-Cambridge Press; MIT OpenCourseWare RES.18-001) §13.2 Partial Derivatives, #39 · Multivariable Calculus · Partial derivatives

The basic _wave equation_ is

The basic _wave equation_ is $f_{tt} = f_{xx}$ . Verify that $f (x, t) = sin (x + t)$ and $f (x, t) = sin (x - t)$ are solutions. Draw both graphs at $t = π /4$ . Which wave moved to the left and which moved to the right?

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Gilbert Strang, Calculus, 3rd edition (Wellesley-Cambridge Press; MIT OpenCourseWare RES.18-001) · §13.2 Partial Derivatives, #39

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