Question

Постройте графиг квадратичной функции y=3x2-7x+4=0

Answer 1

$y=3x^2-7x+4, \ \ a=3>0, \ \ x_0=- frac{-7}{2cdot3}=frac{7}{6}=1frac{1}{6}approx1,2, \ y_0=- frac{(-7)^2-4cdot3cdot4}{4cdot3}=- frac{49-48}{12}=- frac{1}{12}approx-0,1, \ (1frac{1}{6};- frac{1}{12}); \ \ x=0, y=3cdot0-7cdot0+4=4, \ (0;4); \ \ y=0, 3x^2-7x+4=0, \ D=(-7)^2-4cdot3cdot4=1, \ x_1=frac{-(-7)-sqrt{1}}{2cdot3}=frac{7-1}{6}=1, \ x_2=frac{-(-7)+sqrt{1}}{2cdot3}=frac{7+1}{6}=frac{8}{6}=1 frac{1}{3}approx1,3, \ (1;0), (1frac{1}{3};0).$