Question

Fie f,g : R --> R, F(x) = x la puterea 2 - 8x + 12, g(x) = -x

Rezolvati ecuatiile f(x)= 0, f(x) = g(x), g(x)= 0 in R.

Answer 1

Răspuns:

Explicație pas cu pas:

f(x) = x^2 - 8x + 12

f(x) = 0

x^2 - 8x + 12 = 0

Δ = 64 - 4*12 = 64 - 48 = 16

x1 = (8 + 4)/2 = 6

x2 = (8 - 4)/2 = 2

________

f(x) = g(x)

x^2 - 8x + 12 = -x

x^2 - 8x + x + 12 = 0

x^2 - 7x + 12 = 0

Δ = 48 - 4*12 = 49 - 48 = 1

x1 = (7 + 1)/2 = 4

x2 = (7 - 1)/2 = 3

________

g(x) = -x

g(x) = 0

-x = 0

x = 0