The set of eigenfunctions $\sqrt{\frac{2}{1}} \sin \frac{\mathrm{n} \pi \mathrm{x}}{\mathrm{a}}(0 \leq \mathrm{x} \leq \mathrm{a}, \mathrm{n}=1,2,3 )$ is
(a)orthogonal
(b)normalized
(c)both orthogonal and normalized
(d)unnormalized
Answer
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