Question

Determine os zeros da função f(x)=x2+x-30?

Answer 1

Resposta:

Explicação passo-a-passo:

$Aplicando~a~f\'{o}rmula~de~Bhaskara~para~x^{2}+x-30=0~~\\e~comparando~com~(a)x^{2}+(b)x+(c)=0,~temos~a=1{;}~b=1~e~c=-30\\\\\Delta=(b)^{2}-4(a)(c)=(1)^{2}-4(1)(-30)=1-(-120)=121\\\\x^{'}=\frac{-(b)-\sqrt{\Delta}}{2(a)}=\frac{-(1)-\sqrt{121}}{2(1)}=\frac{-1-11}{2}=\frac{-12}{2}=-6\\\\x^{''}=\frac{-(b)+\sqrt{\Delta}}{2(a)}=\frac{-(1)+\sqrt{121}}{2(1)}=\frac{-1+11}{2}=\frac{10}{2}=5\\\\S=\{-6,~5\}$