Question

Resolva as equações do 2 grau ​

Answer 1

Resposta:

a)

x*(x+5)=0

x=0

x+5=0 ==>x=-5

b)

-x*(x-12)=0

-x=0 =+>x=0

x-12=0 ==>x=12

c)

x=0

d)

x'=[2+√(4+32)]/2=(2+6)/2=4

x''=[2-√(4+32)]/2=(2-6)/2=-2

e)

x'=[7+√(49+32)]/4=(7+9)/4=4

x'=[7-√(49+32)]/4=(7-9)/4=-1/2

f)

2*(x+1)^2=-8-3x

2x²+4x+2=-8-3x

2x²+7x+10=0

Δ=49-80< 0  ..não tem raízes Reais

g)

x'=[3+√(9+40)]/2=(3+7)/2=5

x''=[3-√(9+40)]/2=(3-7)/2=-2

h)

x²=2^10

x=±√32

x=-32

x=32

i)

x²=5

x=±√5

j)

x'=[10+√(100-36)]/6=(10+8)/6=3

x''=[10-√(100-36)]/6=(10-8)/6=13

k)

x²-1=224

x²=225

x=±√225

x=±15

l)

2x*(1-x)+4-(-4x²+10x+10)=(x-3)²

2x-2x²+4+4x²-10x-10=x²-6x+9

x²-2x-15=0

x'=[2+√(4+60)]/2=(2+8)/2=5

x''=[2-√(4+60)]/2=(2-8)/2=-3