Question

1- Considere a equação abaixo e faça o que se pede: 2x2-4x-1-0)A) Identifique os coeficientes A, B e C) B)Calcule o discriminante △= b²-4ac) C)Determine o valor de X1 e X2

Answer 1

a)

O coeficiente "a" multiplica o termo x², o coeficiente "b" multiplica o termo x e o coeficiente "c" é o termo independente.

Sendo assim:

a = 2

b = -4

c = -1

b)

△= b²-4ac

△= (-4)² - 4 . 2 . (-1)

△= 16 + 8

△= 24

c)

$x=\frac{-b\pm\sqrt{\Delta}}{2a}\\\\\\x_1=\frac{-b+\sqrt{\Delta}}{2a}\\\\x_1=\frac{4+\sqrt{24}}{2.2}\\\\x_1=\frac{4+\sqrt{2^2.6}}{4}\\\\x_1=\frac{4+2\sqrt{6}}{4}\\\\x_1=\frac{2+\sqrt{6}}{2}$

$x_2=\frac{-b-\sqrt{\Delta}}{2a}\\\\x_2=\frac{4-\sqrt{24}}{2.2}\\\\x_2=\frac{4-\sqrt{2^2.6}}{4}\\\\x_2=\frac{4-2\sqrt{6}}{4}\\\\x_2=\frac{2-\sqrt{6}}{2}$