Respuesta :

[tex]▪▪▪▪▪▪▪▪▪▪▪▪▪  {\huge\mathfrak{Answer}}▪▪▪▪▪▪▪▪▪▪▪▪▪▪[/tex]

Question : 14

let's solve for f :

  • [tex] \dfrac{1}{f} = \dfrac{1}{a} + \dfrac{1}{b} [/tex]

  • [tex] \dfrac{1}{f} = \dfrac{b + a}{ab} [/tex]

Taking reciprocal of both sides :

  • [tex]f = \dfrac{ab}{a + b} [/tex]