Question

wyznacz pierwiastki trójmianu klwadratowego y= 3x^ + 2x-1

Answer 1

y = 3x² + 2x - 1

 

a = 3 , b = 2 , c = - 1

 

Δ = b² - 4·a·c

 

Δ = 2² - 4 · 3 · (-1)

Δ = 4 + 12 = 16

√Δ = 4

 

 

 

 

 

x₁ = - 1

 

 

 

 

 

Odp: pierwiastku trójmianu to: x₁= -1 i x₂ = ⅓

Answer 2

DELTA = ?
a= 3
b= 2
c= -1

DELTA = b^2 - 4ac
DELTA = 2^2 - 4 x 3 x (-1)
DELTA = 4 + 12
DELTA = 16
\sqrt{DELTA} = 16
DELTA = 4
DELTA > 0

      -b - \sqrt{DELTA}
x1= ---------------------
                 2a
       
        -2 - 4
x1 = ---------

         2 x 3

 

           -6
x1 = ---------
            6

x1 = -1

        -b + \sqrt{DELTA}
x2 = ----------------------
                   2a

 

        -2 + 4
x2 = ---------
            6

        2      1
x2 = --- = ---
        6      3