By taking the Fourier transform of the equation
d^2φ/dx^2-K^2φ=f(x)
Show that the solution \phi(x) can be written as:
\phi(x) = \frac{1}{\sqrt{2\pi}} \int_{-\infty}^{\infty} \tilde{\phi}(k) e^{ikx} \, dk
Mathbot Says...
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