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Years: 1246 1247 1248 1249 1250 - 1251 - 1252 1253 1254 1255 1256
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... so we add the square of b/(2a) to both sides, getting <math>x^2+\frac{b}{a}x+\frac{b^2}{4a^2}=-\frac{c}{a}+\frac{b^2}{4a^2}.</math> The left side is ...