We deduce the exact Jackson-type inequalities for the approximations of functions ƒ ∈ L 2(ℝ) in L 2(ℝ) by using partial sums of wavelet series in the cases of Meyer and Shannon-Kotelnikov wavelets.
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Translated from Ukrains'kyi Matematychnyi Zhurnal, Vol. 60, No. 8, pp. 1119–1127, August, 2008.
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Babenko, V.F., Zhiganova, G.S. On the best L 2-approximations of functions by using wavelets. Ukr Math J 60, 1307–1317 (2008). https://doi.org/10.1007/s11253-009-0124-1
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DOI: https://doi.org/10.1007/s11253-009-0124-1