Question

A menor raiz real da equação do 2° grau -2x² + 9x - 4=0 é:

Answer 1

$x= \frac{ -b_{-}^+\sqrt{b^2- 4.a.c}}{2.a} \\ \\ x= \frac{ -9_{-}^+\sqrt{9^2- 4.(2).(-4)}}{2.(-2)} \\ \\ x= \frac{ -9_{-}^+\sqrt{81- 32}}{-4} \\ \\ x= \frac{ -9_{-}^+\sqrt{81- 32}}{-4} \\ \\ x= \frac{ -9_{-}^+\sqrt{49}}{-4} \\ \\ x= \frac{ -9_{-}^+{7}}{-4} \\ \\ x^I= \frac{-9+7}{-4} = \frac{-2}{-4} = 0,5 \\ \\ x^I^I= \frac{-9-7}{-4} = \frac{-16}{-4} =4$


$Menor: x^I=0,5$