5x²+mx-12 = 0 |:5
x²+0.2mx-12/5 = 0
Теорема Виета:
{x1+x2 = -1/5m
{x1•x2 = -12/5
x2 = -12/5:x1 = -12/5 • (-1/3) = 4/5
x1+x2 = 4/5 - 3 = -11/5 = -1/5m
m = 11•5/5 = 11
ответ: x2 = 0.8, m = 11
5x²+mx-12 = 0 |:5
x²+0.2mx-12/5 = 0
Теорема Виета:
{x1+x2 = -1/5m
{x1•x2 = -12/5
x2 = -12/5:x1 = -12/5 • (-1/3) = 4/5
x1+x2 = 4/5 - 3 = -11/5 = -1/5m
m = 11•5/5 = 11
ответ: x2 = 0.8, m = 11