Gullspång is a municipality in southwest Sweden, in the county of Västra Götaland. The municipality covers an area of 313.0 km². Of the total population of 5911, 2999 are male, and 2912 are female. The population density of the community is 19 inhabitants per km².
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The formula and its proof remain correct if the coefficients a, b and c are complex numbers, or more generally members of any field whose characteristic is not 2. ...