Question

Log (2x² + 11 x - 4) = log ( x² - 13)​

Answer 1

Resposta:

$\text{Leia abaixo}$

Explicação passo-a-passo:

$log\:(2x^2 + 11x - 4) = log\:(x^2 - x - 13)$

$2x^2 + 11x - 4 = x^2 - x - 13$

$x^2 + 10x + 9 = 0$

$\Delta = b^2 - 4.a.c$

$\Delta = 10^2 - 4.1.9$

$\Delta = 100 - 36 = 64$

$x' = \dfrac{-10 + \sqrt{64}}{2} = \dfrac{-10 + 8}{2} = -1$

$x'' = \dfrac{-10 - \sqrt{64}}{2} = \dfrac{-10 - 8}{2} = -9$

$\boxed{\boxed{\text{S} = \left\{-1,-9\right \}}}}$