Question

log(4-x)/log(x+2) = 2

Answer 1

Respuesta:

Respuesta: x = 0

Explicación paso a paso:

log(4-x)/log(x+2) = 2

log(4-x) = 2 . log(x+2)

log(4-x) = log(x+2)²

4 - x = (x+2)²

4 - x = x² + 4x + 4

0 = x² + 4x + 4 - 4 + x

0 = x² + 5x

0 = x.(x+5)

x₁ = 5

x + 5 = 0

x₂ = -5

• VERIFICACIÓN:

• con x₁ = 0

log(4-0)/log(0+2) = 2

log 4/log 2 = 2

log 4 = 2 . log 2

log 4 = log 2²

log 4 = log 4        VERIFICA

• con x₂ = -5

log(4-(-5))/log(-5+2) = 2

log 9/ log (-3) = 2   NO VERIFICA porque log(-3) no existe