Question

Como resolver: 3x² +5x - 2 = 0

Answer 1

Resposta:

$\textsf{Leia abaixo}$

Explicação passo a passo:

$\mathsf{3x^2 + 5x - 2 = 0}$

$\mathsf{\Delta = b^2 - 4.a.c}$

$\mathsf{\Delta = (5)^2 - 4.3.(-2)}$

$\mathsf{\Delta = 25 + 24}$

$\mathsf{\Delta = 49}$

$\mathsf{x = \dfrac{-b \pm \sqrt{\Delta}}{2a} = \dfrac{-5 \pm \sqrt{49}}{6} \rightarrow \begin{cases}\mathsf{x' = \dfrac{-5 + 7}{6} = \dfrac{2}{6} = \dfrac{1}{3}}\\\\\mathsf{x'' = \dfrac{-5 - 7}{6} = \dfrac{-12}{6} = -2}\end{cases}}$

$\boxed{\boxed{\mathsf{S = \left\{\dfrac{1}{3};-2\right\}}}}$

Answer 2

Explicação passo-a-passo:

3x² +5x - 2 = 0

a=3

b=5

c=-2

∆=b²-4ac

∆=5²-4×3×-2

∆=25+24

∆=49

-b±√∆/2a

-5±√49/2×3

-5±7/6

x¹=-5+7/6=2/6(÷2)=>1/3

x²=-5-7/6=-12/6=>-2