Question

Fórmula do Bhaskara

1)determine o conjunto verdade das equações do 2° grau:
a)x²+5x+6=0 a=1 b=5 c=6
∆=
∆=
∆=
∆=
b)x²-8x+15=0
∆=
∆=
∆=
∆=
c)3x²+4x+1=0
∆=
∆=
∆=
∆=
d)-x²+12x-20=0
∆=
∆=
∆=
∆=

Answer 1

a)x²+5x+6=0

∆= (-b ± $\sqrt{b² -4ac}$)/2a

∆= (-5 ± $\sqrt{5²-4.1.6}$)/2.1

∆= (-5 ± $\sqrt{25-24}$)/2

∆= (-5 ± 1 ) / 2

x1= -3

x2= -2

b)x²-8x+15=0

∆= (-b ± $\sqrt{b² -4ac}$)/2a

∆= (-(-8) ± $\sqrt{(-8)² -4.1.15}$)/2.1

∆= (8 ± $\sqrt{64 - 60}$)/2

∆= (8 ± 2)/2

x1=5

x2=3

c)3x²+4x+1=0

∆= (-b ± $\sqrt{b² -4ac}$)/2a

∆= (-4 ± $\sqrt{4² - 4.3.1}$)/2.3

∆= (-4 ± $\sqrt{16 - 12}$)/6

∆= (-4 ± $\sqrt{4}$)/6

∆= (-4 ± 2)/6

x1= -1

x2= -1/3

d)-x²+12x-20=0

∆= (-b ± $\sqrt{b² -4ac}$)/2a

∆= (-12 ± $\sqrt{12² -4.(-1).(-20)}$)/2.(-1)

∆= (-12 ± $\sqrt{144 - 80)}$)/-2

∆=(-12 ± $\sqrt{64}$)/-2

∆=(-12 ± 8)/-2

x1=10

x2=2