Question

Решить систему уравнений

Answer 1

$1)frac{-3+sqrt{21} }{6}+frac{-3-sqrt{21} }{6}=frac{-3+sqrt{21}-3-sqrt{21}}{6}=frac{-6}{6}=-1\\-frac{b}{a}=-1\\a=b\\2)frac{-3+sqrt{21} }{6} *frac{-3-sqrt{21} }{6} =frac{(-3+sqrt{21})(-3-sqrt{21})}{6*6}=frac{(-3)^{2}-(sqrt{21})^{2}}{36}=frac{9-21}{36}=-frac{12}{36}=-frac{1}{3}\\frac{c}{a}=-frac{1}{3}\\c=-1\\a=b=3$