The removal of $\pi $ from some undecidable problems involving elementary functions
نویسندگان
چکیده
منابع مشابه
The Removal of Π from Some Undecidable Problems Involving Elementary Functions
We show that in the ring generated by the integers and the functions x, sinxn and sin(x · sinxn) (n = 1, 2, . . .) defined on R it is undecidable whether or not a function has a positive value or has a root. We also prove that the existential theory of the exponential field C is undecidable. 1. Let S denote the class of expressions generated by the rational numbers and π, the variable x, the op...
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 2002
ISSN: 0002-9939,1088-6826
DOI: 10.1090/s0002-9939-02-06753-9