Respuesta :

Answer:

R =  [tex]\frac{6}{23}[/tex]

Step-by-step explanation:

Given the rational equation as:

[tex]\frac{1}{R}=\frac{1}{x}+\frac{1}{y}[/tex]

To find:

The value of R when x = [tex]\frac{\textup{2}}{\textup{5}}[/tex]

and, y = [tex]\frac{\textup{3}}{\textup{4}}[/tex]

now,

substituting the given values of x and y in the given rational equation,

[tex]\frac{1}{R}=\frac{1}{\frac{2}{5}}+\frac{1}{\frac{3}{4}}[/tex]

or

⇒ [tex]\frac{1}{R}=\frac{5}{2}+\frac{4}{3}[/tex]

or

⇒ [tex]\frac{1}{R}=\frac{5\times3+4\times2}{2\times3}[/tex]

or

⇒ [tex]\frac{1}{R}=\frac{15+8}{6}[/tex]

or

⇒ [tex]\frac{1}{R}=\frac{23}{6}[/tex]

now on rearranging, we get

⇒ R =  [tex]\frac{6}{23}[/tex]