Bounds for the first Dirichlet eigenvalue of triangles and quadrilaterals
نویسندگان
چکیده
منابع مشابه
Upper and Lower Bounds for the First Dirichlet Eigenvalue of a Triangle
We prove some new upper and lower bounds for the first Dirichlet eigenvalue of a triangle in terms of the lengths of its sides.
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where j0,1 is the first positive zero of the Bessel function J0, and equality holds for the disk. If we now restrict the class of domains under consideration, it is possible to improve the above result. This can be done in several different ways, of which we shall now discuss some examples. One possibility is to consider the class of n-polygons, for which Pólya and Szegő proposed the following ...
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ژورنال
عنوان ژورنال: ESAIM: Control, Optimisation and Calculus of Variations
سال: 2009
ISSN: 1292-8119,1262-3377
DOI: 10.1051/cocv/2009018