Question

Calcular: (3/7)^-2 + 5/2(7)^-1 + (1/4)^1/2

Answer 1

$(\dfrac{3}{7})^-^2 + \dfrac{5}{2}(7)^-^1 + (\dfrac{1}{4})^ \frac{1}{2}$

Para retirar o sinal de negativo do expoente inverta a fração:

$(\dfrac{7}{3})^2 + \dfrac{5}{2}( \dfrac{1}{7} )^1 + \dfrac{1}{2} \\ \\ \\ \dfrac{49}{9} + \dfrac{5}{14} + \dfrac{1}{2}$

MMC de 9, 14, 2 = 126

$\dfrac{14*49 +9*5 + 63 }{126} \\ \\ \\ \dfrac{686 +45 + 63 }{126} \\ \\ \\ \dfrac{794}{126} => \dfrac{794 \div \ 2}{126 \div \ 2} => \dfrac{397}{63}$