Question

x^2-x=12
a)admite a raiz de -3
b)admite a raiz de 1
c)admite a raiz de -4
d)nao admite a raizes reais

Answer 1

boa tarde!!!!


X² - X = 12

X² - X + ( 1/2 )² = 12 + ( 1/2)²

( X - 1/2 )² = 49/4


X' = -3
X" = 4

S = { - 3 e 4 }


Alternativa A)



espero ter ajudado!!!

Answer 2

Olá, aplicando pelo delta

x² - x - 12 = 0

∆= 1 + 49

∆= 49

x' = 1 + √49/2 = 1+7/2 = 4

x" = 1 - √49/2 = 1-7/2 = -3

Correta A)