Question

1/f=1/a+1/b solve for f

Answer 1

Greetings!

"Solve for f: $1/f=1/x+1/y$".

Multiply both sides by f.
$(1/f)*f=(1/x+1/y)*f$
Simplify.
$1=(fx+fy)/xy$
Multiply both sides by xy.
$(1)*xy=((xf+yf)/xy)*xy$
Simplify.
$xy=xf+yf$
Factor out f.
$xy=f(x+y)$
Divide both sides by x+y.
$(xy)/x+y=(f(x+y))/x+y$
Simplify.
$(xy)/(x+y)=f$
$f=(xy)/(x+y)$

Had to change the variable as Brainly thought it was a swearword. Sorry.

Hope this helps.
-Benjamin