→ cgkm :未證先猜 dim(V) = max{n-k, 0} 11/20 04:23
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設X1, X2, ..., Xn之多項式U(X1, X2, ..., Xn)滿足
(1) U(t X1,t X2,...,t Xn)= t^k U(X1, X2, ..., Xn), k為已知正整數
(2) U11+U22+...+Unn = 0 (二階偏導函數總和=0, 即Laplace eq.)
這些函數U(X1, X2, ..., Xn)形成一個vector space V over R
試求 dim(V) (以 n, k表示)
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