Предмет: Алгебра, автор: виктория12062000

не решая уровнения найдите х1+х2 и х1*х2 а) х^2 + 2x - 6 = 0 б) 2х^2 -13x+9=0

Ответы

Автор ответа: vikochkafomina
0
Ну мне кажется , что правильный ответ под буквой а
Автор ответа: m11m
1
а) х²+2х-6=0
   а=1    b=2    c=-6
По т.Виета:
х₁+х₂=-b            x₁*x₂= c
           a                      a
x₁+x₂=-2
x₁*x₂=6

б) 2х²-13х+9=0
а=2    b=-13    c=9
x₁+x₂=-(-13) =6.5
             2
x₁*x₂=9 = 4.5
         2
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