diketahuif(x)=1/akar x maka tentukan nilai dari -2f(x)

semoga bisa membantu

................1
f(x) = ------------
.............akar x
..........................1
-2 f(x) = -2 × -----------
........................akar x
....... -2
= ------------
.....akar x
.......-2............akar x
= ----------- ×-------------
....akar x........akar x
.... -2 akar x
= ----------------
.............x
..... -2
= -------- × akar x
.......x