Question

x² +X-1=0 a resposta??????

Answer 1

Resposta:

Explicação passo-a-passo:

$\displaystyle Aplicando~a~f\'{o}rmula~de~Bhaskara~para~x^{2}+x-1=0~~\\e~comparando~com~(a)x^{2}+(b)x+(c)=0,~temos~a=1{;}~b=1~e~c=-1\\\\\Delta=(b)^{2}-4(a)(c)=(1)^{2}-4(1)(-1)=1-(-4)=5\\\\x^{'}=\frac{-(b)-\sqrt{\Delta}}{2(a)}=\frac{-(1)-\sqrt{5}}{2(1)}=\frac{-1-\sqrt{5}}{2}\\\\x^{''}=\frac{-(b)+\sqrt{\Delta}}{2(a)}=\frac{-(1)+\sqrt{5}}{2(1)}=\frac{-1+\sqrt{5}}{2}=\\\\S=\{\frac{-1-\sqrt{5}}{2},~\frac{-1+\sqrt{5}}{2}\}$

Answer 2

x1 = - 1 - √5. -1+√5

–––––– , x2 = ––––––

2. 2