Powys is one of eight counties in Wales, over 2000 sq. m. in size, and consisting of the former counties of Montgomeryshire[?], Radnorshire[?] and Brecknockshire[?].
This county is named for the older Welsh kingdom of Powys, which occupied roughly the same area, which came to an end when it was absorbed into the kingdom of Gwynedd by Hywel Dda.
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<math>\pm \sqrt {b^2-4ac}</math>
in the formula should be understood as "either of those element(s) of the field whose square equals b2 - 4ac". In some ...