Question

resolva a equação 0=x2-2x-3

Answer 1

x² - 2x - 3

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

Δ = 4 - 4 . 1 . ( - 3)
Δ = 4 + 12
Δ = 16

$x= \dfrac{-b \pm \sqrt{\Delta} }{2a} \\\\\\\\x= \dfrac{2 \pm \sqrt{16} }{2} \\\\\\x'=3\\\\x''=-1$


Forte abraço!

Answer 2

Olá, boa noite ☺

Resolução:

x²-2x-3=0

Coeficientes:

a=1
b=-2
c=-3

Valor do discriminante:

Δ=b²-4.a.c
Δ=(-2)²-4.1.(-3)
Δ=4+12
Δ=16

Valore de x:

$\\\text{x}= \dfrac{\text{-b}\pm \sqrt{\Delta} }{\text{2.a}} \\ \\ \text{x} = \dfrac{\text{2}\pm\text{4}}{\text{2}} \\ \\ \text{x'} = \dfrac{\text{2+4}}{\text{2}} =\text{3} \\ \\ \text{x''}= \dfrac{\text{2-4}}{2} =\text{-1}$

S={3,-1}

Bons estudos :)