Question

Gente me ajudem!!
Sabe-se que

$T= \frac{1}{ \frac{1}{x} + \frac{1}{y} }$

e q x=4 y=5 
quanto vale T
       
                             

Answer 1

$T = \frac{1}{ \frac{1}{4}+ \frac{1}{2} } \\ \\ T = \frac{1}{ \frac{1+2}{4} } \\ \\ T = \frac{1}{ \frac{3}{4} } \\ \\ T = 1x \frac{4}{3} = \frac{4}{3}$

Answer 2

para
x=4
y=5

$T= \frac{1}{ \frac{1}{x}+ \frac{1}{y} } \\ \\ T= \frac{1}{ \frac{5+4}{20} } \\ \\ T= \frac{1}{ \frac{9}{20} } \\ \\ T=1\div \frac{9}{20} =1\times \frac{20}{9} \\ \\ T= \frac{20}{9}$