Question

resolva as equações do segundo grau, sendo U=IR:
a) 2x²-2x-12=0
b) -x²+5x-6=0
c) -2x²-10x-12=0
d) x²+x-6=0​

Answer 1

a)(-2)^2×(-4)×(2)×(-12)=100. x1=3,x2=--2. b)(5)^2-4×(-1)×(-6)=1. x1=2,x2= 3.

c)(-10)^2-4×(-2)×(-12).x1=-3,x2=-2. d)(1)^2-4×(1)×(-6)=25.x1=2,x2= -3.

Answer 2

Resposta:

Explicação passo-a-passo:

A)2x-2x-12=0

∆=b²-4ac

∆=(-2)²-4.2.(-12)

∆=4-(-96)

∆=100

X=-b±√∆/2a

X=-(-2)±√100/2.2 X=-8/4=-2

X=2±10/4 X=12/4=3

S{-2;4}

B)-x²+5x-6=0

∆=b²-4ac

∆=5²-4.(-1).(-6)

∆=25-24

∆=1

X=-b±√∆/2a

X=-5±√1/2.(-1) X=-6/-2=3

X=-5-1/-2 X=-2/1=2

S{3;2}

C)-2x²-10x-12=0

∆=b²-4ac

∆=(-10)²-4.(-2).(-12)

∆=100-96

∆=4

X=-b±√∆/2a

X=-(-10)±√4/2.(-2) X=8/-4=-2

X=10±2/-4 X=12/-4=-4

S{-2;-4}

D)x²+x-6=0

∆=b²-4ac

∆=1²-4.1.(-6)

∆=1-(-24)

∆=25

X=-b±√∆/2a

X=-1±√25/2.1 X=-6/2=-3

X=-1±5/2 X=4/2=2

S{-3;2}