К.Ю. Богачёв - Практикум на ЭВМ. Методы приближения функций (1133845), страница 20
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.1 1.1 >.-95<. (I.1.3)2.3.45 65/78/+8 5/-79:+6;<55 { 735/54/.;, -+ i = f (xi yi), i = 1 2 : : : 10 5:95C65?.FG.; @H/1<5; 5>77- 053Pf (x y) =10Xi=1f (xi yi)'i(x y):/.47/5; :95C65?.FG78 @H/1<55 Pf /. ,-+9+/7 -97H=+6B/51. (/.:95>79,S(x1 y1) (x2 y2)]) +:97376;F-,; -+6B1+ 2/.47/5;>5 @H/1<55 f 0 -+41.A, 67?.G5A /. I-+8 ,-+9+/7 (0 /.E7> :95>797 { (x1 y1), (x2 y2), (x1 2 1 y1 2 1) 5(x1 2 2 y1 2 2)).
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