Question

dada a função f(x) = x2-3x-10, f(x) = 0 quando:

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Answer 1

Resposta:

f(x)=x²+3x-10

a)f(0)=0²+3.0-10= 0+0-10= -10

b)f(-1)=(-1)²+3.(-1)-10= 1 -3 -10= -2-10= -12

c)f(2)=2²+3.2-10= 4+6-10=10-10=0

d)0=x²+3x-10

∆=3²-4.1.(-10)

∆=9+40

∆=49

x= -3±√49/2.1

x= -3±7/2

x1= -3+7/2= 4/2=2

x2= -3-7/2= -10/2= -5

e) -6=x²+3x-10

x²+3x-10+6=0

x²+3x-4=0

∆= 3²-4.1.(-4)

∆=9+16

∆=25

x= -3±√25/2.1

x= -3±5/2

x1= -3+5/2=2/2=1

x2= -3-5/2=-8/2=-4