Question

quando x= -2/3, o valor numérico da expressão 3x² - x - 2 é?

Answer 1

Explicação passo-a-passo:

Substituindo:

3.-2/3 - (-2/3) - 2

-6/3 + 2/3 - 2

-4/3 - 2/1

-4/3 - 6/3

-10/3

Answer 2

$\mathsf{3{x}^{2}-x-2\big|_{x=\frac{2}{3}}=3.{(-\dfrac{2}{3})}^{2}-(-\dfrac{2}{3})-2}\\\mathsf{\cancel{3}.\dfrac{4}{\cancel{9}}+\dfrac{2}{3}-2}\\\mathsf{\dfrac{4}{3}+\dfrac{2}{3}-2=2-2}$

$\boxed{\boxed{\mathsf{3{x}^{2}-x-2\big|_{x=\frac{2}{3}}=0}}}$