Question

x^-x-1 com armaçao e formula de baskara com duas raizes

Answer 1

Olá!!!

x² - x - 1 = 0

a = 1, b = - 1 , c = - 1

∆ = b² - 4ac
∆ = ( - 1 )² - 4 • 1 • ( - 1 )
∆ = 1 + 4
∆ = 5

x = - b ± √5 / 2a
x = - ( - 1 ) ± √5 / 2 • 1
x = 1 ± √5 / 2
x' = 1 + √5 / 2
x'' = 1 - √5 / 2


Espero ter ajuado...

Answer 2

Ola!!

Têm-se a equação:

${\color{blue}{x^2-x-1=0}}$

$Coeficientes:\left\{\begin{array}{cc}a=1\\b=-1\\c=-1\\\end{array}\right$

Lembrando que:

$\Leftrightarrow\:\Delta=b^2-4*a*c$

$\Leftrightarrow\:\Delta=(-1)^2-4*1*(-1)$

$\Leftrightarrow\:\Delta=1+4$

${\color{blue}{\Leftrightarrow\:\Delta=5}}$

$\large\boxed{\boxed{{x_{1,2}=\frac{-b\pm\sqrt{\Delta}}{2*a}}}}}}$

Logo:

$x_{1,2}=\frac{1\pm\sqrt{5}}{2*1}$

$x_{1,2}=\frac{1\pm\sqrt{5}}{2}$