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 è è è7ê±sZ?￥'?′ù5 r2u(r)+?u(r) = 0; r2 V u(r)flfl§ = 0 x21.4±sZ??3ù5?'?′ù5￥Ms? T?16: ￥Ms? T
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 V¨[ T?  yn(x) =fi1?1?x2￠+fi2?1?x2￠2 +fi3?1?x2￠3 + ￠￠￠+fin?1?x2￠n; n = 1;2;3;￠￠￠ ?/í'?f ?
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 ¤ I[y2] = Z 1 0 xy022 dx=fi21 + 43fi1fi2 + 23fi22; I1[y2] = Z 1 0 xy22 dx = 16fi21 + 14fi1fi2 + 110fi22 = 1: x21.5 Rayleigh–RitzZE?19: ? V[ A? ^fi1?fi2￥=íf ?￥Hq′ù5
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