Question

Найти коэффициент с уравнения:
12x^2+bx+c=0
Корни:3.25;-1/4

Answer 1

По теореме Виета:

$x_{1}\cdot x_{2}=\frac{c}{12}$

$3,25\cdot (-\frac{1}{4})=\frac{c}{12} \\\\3\frac{1}{4}\cdot (-\frac{1}{4})=\frac{c}{12}\\\\\frac{13}{4}\cdot (-\frac{1}{4})=\frac{c}{12}\\\\-\frac{13}{16}=\frac{c}{12} \\\\-13\cdot 12=16c\\\\c=-\frac{39}{4}\\\\ c=-9\frac{3}{4}$