Question

(VALENDO 40 PONTOS) Calcule o valor numérico das expressões: (foto)

Answer 1

$\dfrac{a^2 + b^3}{2} \\ \\ \\ \dfrac{(-1)^2 +(-2)^3}{2} \\ \\ \\ \dfrac{1 +(-8)}{2} \\ \\ \\ \dfrac{1 -8}{2} \\ \\ =\ \textgreater \ -\dfrac{7}{2}$

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$\dfrac{ab + c}{ab - c} \\ \\ \\ \dfrac{2 . 5 + 3}{2.5 - 3} \\ \\ \\ \dfrac{10 + 3}{10 - 3} \\ \\ \\ =\ \textgreater \ \dfrac{13}{7}$

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$\dfrac{a + b}{3} + \dfrac{2a}{5} \\ \\ \\ \dfrac{1 + (-7)}{3} + \dfrac{2.1}{5} \\ \\ \\ \dfrac{1 -7}{3} + \dfrac{2}{5} \\ \\ \\ \dfrac{-6}{3} + \dfrac{2}{5} \\ \\ \\ \dfrac{3.-6 + 3.2}{15} \\ \\ \\ \dfrac{-30 + 6}{15} \\ \\ \\ \dfrac{-24}{15} \\ \\ \\ =\ \textgreater \ -\dfrac{8}{5}$

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$\dfrac{x^2 + 2xy + y^2}{x - y} \\ \\ \\ \dfrac{1^2 + 2. 1 . \dfrac{1}{2} + (\dfrac{1}{2})^2}{1 - \dfrac{1}{2}} \\ \\ \\ \dfrac{1 + 2. \dfrac{1}{2} + \dfrac{1}{4}}{\dfrac{1}{2}} \\ \\ \\ \dfrac{1 + \dfrac{2}{2} + \dfrac{2}{4}}{\dfrac{1}{2}} \\ \\ \\ \dfrac{1 + 1 + \dfrac{2}{4}}{\dfrac{1}{2}} \\ \\ \\ \dfrac{2 + \dfrac{2}{4}}{\dfrac{1}{2}} \\ \\ \\ \dfrac{\dfrac{9}{4}}{\dfrac{1}{2}} \\ \\ \\ \dfrac{9}{4} . \dfrac{2}{1} \\ \\ \\ =\ \textgreater \ \dfrac{9}{2}$