Introduction 1. Approximation with nodes............................................................................................. 3 2. Characteristic property of the optimal polynomial......................................................... 4 3. Notation......................................................................................................................... 5 CHAPTER I. Limit properties of approximation with nodes 4. Statement of the problem.............................................................................................. 7 6. Qualitative results.......................................................................................................... 8 6. Quantitative results...................................................................................................... 11 7. The case of two nodes................................................................................................. 23 CHAPTER II. System of optimal polynomials 8. Necessary and sufficient conditions in approximation without nodes.......................... 38 9. Corollaries.................................................................................................................... 46 10. Necessary and sufficient conditions in approximation with nodes............................. 52 References....................................................................................................................... 62
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