Question

resolva as equações do 2 grau em R 2x(4x-2)-4=0

Answer 1

2x(4x-2)-4=0
8x²-4x-4=0

Δ = b² - 4.a.c 
Δ = -4² - 4 . 8 . -4 
Δ = 16 - 4. 8 . -4 
Δ = 144

x = (-b +- √Δ)/2a

x' = (--4 + √144)/2.8         x'' = (--4 - √144)/2.8
x' = 16 / 16                        x'' = -8 / 16
x' = 1                                  x'' = -0,5

Answer 2

$2x(4x-2)-4=0 \\ \\ 8x^2-4x-4=0 \\ \\ a=8 \\ b=-4 \\ c=-4 \\ \\ \Delta=b^2-4ac \\ \Delta=(-4)^2-4(8)(-4) \\ \Delta=16+128 \\ \Delta=144 \\ \\ x= \frac{-b\pm \sqrt{\Delta} }{2a} \\ \\ x= \frac{-(-4)\pm \sqrt{144} }{2.(8)} = \frac{4\pm12}{16} \\ \\ x'= \frac{4+12}{16} = \frac{16}{16} =1 \\ \\ x"= \frac{4-12}{16} =- \frac{8}{16} =- \frac{1}{2}$