Uniform and C1-approximability of functions on compact subsets of ℝ2 by solutions of second-order elliptic equations. / Paramonov, P. V.; Fedorovskiǐ, K. Yu.
In: Sbornik Mathematics, Vol. 190, No. 1-2, 1999, p. 285-307.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Uniform and C1-approximability of functions on compact subsets of ℝ2 by solutions of second-order elliptic equations
AU - Paramonov, P. V.
AU - Fedorovskiǐ, K. Yu
PY - 1999
Y1 - 1999
N2 - Several necessary and sufficient conditions for the existence of uniform or C1-approximation of functions on compact subsets of ℝ2 by solutions of elliptic systems of the form c11ux1x1 + 2c12ux1x2 + c22ux2x2 = 0 with constant complex coefficients c11, c12, and c22 are obtained. The proofs are based on a refinement of Vitushkin's localization method, in which one constructs localized approximating functions by 'gluing together' some special many-valued solutions of the above equations. The resulting conditions of approximation are of a topological and metric nature.
AB - Several necessary and sufficient conditions for the existence of uniform or C1-approximation of functions on compact subsets of ℝ2 by solutions of elliptic systems of the form c11ux1x1 + 2c12ux1x2 + c22ux2x2 = 0 with constant complex coefficients c11, c12, and c22 are obtained. The proofs are based on a refinement of Vitushkin's localization method, in which one constructs localized approximating functions by 'gluing together' some special many-valued solutions of the above equations. The resulting conditions of approximation are of a topological and metric nature.
UR - http://www.scopus.com/inward/record.url?scp=0033451151&partnerID=8YFLogxK
U2 - 10.1070/sm1999v190n02abeh000386
DO - 10.1070/sm1999v190n02abeh000386
M3 - Article
AN - SCOPUS:0033451151
VL - 190
SP - 285
EP - 307
JO - Sbornik Mathematics
JF - Sbornik Mathematics
SN - 1064-5616
IS - 1-2
ER -
ID: 86670029