Question

Determine os pontos que o gráfico passam pelo eixo das abscissas das funções a) F(x)=x^2+x-2

Answer 1

$f(x)=x^2+x-2 \\ \\ x^{2} +x-2=0 \\ \\ a=1 \\ b=1 \\ c=-2 \\ \\ \Delta=b^2-4ac \\ \Delta=(1)^2-4(1)(-2) \\ \Delta=1+8 \\ \Delta=9 \\ \\ x= \frac{-b\pm \sqrt{\Delta} }{2a} \\ \\ x= \frac{-1\pm \sqrt{9} }{2} = \frac{-1\pm3}{2} \\ \\ x'= \frac{-1-3}{2} =- \frac{4}{2} =-2 \\ \\ x"= \frac{-1+3}{2} = \frac{2}{2} =1 \\ \\ Os~~pontos~~s\tilde{a}o~~-2~~e~~1$