Question

HELPP ME
Determine as raízes (zeros) reais nas funções a seguir
G(x)=x2+4x+3

H(x)=x2-25

i(x)=x2-8x

Answer 1

g(x) = x^2+4x+3 a= 1 b=4 c= 3
Tirando o delta :
D= b^2-4.a.c
D= 4^2-4.1.3
D= 16-12
D= 4 Raizes =+-2
x = -b +- raiz do delta /2a
X’= 4+ 2/2 = 6/2 = 3
X”= 4-2/2 = 2/2 = 1 Raizes : 1e 3

h(x) = x^2-25
x^2= 25
x = raiz de 25
x = + -5 Raizes : -5, +5

i( x) = x^2-8x
x^2-8x= 0
x( x-8)= 0 Ou x= 0
Ou x-8 = 0
x= 8 Raizes : 0 , 8