Question

Calcule os valores de x na função
g(x) = 2x² + 2x - 12 quando:

a) g(x)= - 8

b) g(x) = -12

c) g(x)=0

pfvr me ajudemmm!!!​

Answer 1

Resposta:

a) S= {-2, 1}

b) S={-1, 0}

c) S={-2, 3}

Explicação passo-a-passo:

Fórmulas utilizadas:

Δ= b²-4ac

x= (-b±√Δ)/2a

a) g(x)= -8

g(x)= 2x² + 2x - 12

-8=2x²+2x-12

-8-2x²-2x+12=0

-2x²-2x+4=0   .(-1)

2x²+2x-4=0

Δ= (2)² - 4.(2).(-4)

Δ= 4+32

Δ=36

x= [-(2)±√36]/2.2

x=[-2±6]/4

x'=[-2+6]/4

x'=4/4

x'= 1

x''=[-2-6]/4

x''=-8/4

x''= -2

S= {-2, 1}

b) g(x)= -12

g(x)= 2x²+2x-12

-12=2x²+2x-12

-12-2x²-2x+12=0

-2x²-2x+0=0  .(-1)

2x²+2x=0

2x(x+1)=0

2x=0

x=0/2

x=0

x+1=0

x= -1

S={-1, 0}

c) g(x)=0

g(x)= 2x²-2x-12

2x²-2x-12=0

Δ=(-2)² -4.(2).(-12)

Δ=4+96

Δ=100

x= [-(-2)±√100]/2.2

x=[2±10]/4

x'=[2+10]/4

x'=12/4

x'= 3

x''=[2-10]/4

x''=-8/4

x''= -2

S={-2, 3}