Question

9. (Ufpel-RS) O valor numérico da expressão ​

Answer 1

Resposta:

Explicação passo a passo:

$1-\frac{1}{x} =\frac{x-1}{x}$

$\frac{1}{\frac{x-1}{x} } =\frac{x}{x-1}$

$1-\frac{x}{x-1} =\frac{x-1}{x-1} -\frac{x}{x-1} =\frac{x-1-x}{x-1} =-\frac{1}{x-1}$

$x=0,45222...=\frac{(452-45)}{900} =\frac{407}{900}$

$y=0,31888...=\frac{(318-31)}{900} =\frac{287}{900}$

$\frac{1}{y} =\frac{900}{287}$

$x-1=\frac{407}{900} -\frac{900}{900} =-\frac{493}{900}$

$-\frac{1}{x-1} =-(-\frac{900}{493})=\frac{900}{493}$

$Portanto\:vai\:ficar\:assim...$

$\frac{900}{287} :\frac{900}{493} =$

$\frac{900}{287} \:.\:\frac{493}{900} =$

$\frac{493}{287}$

$Resposta:(d)$