Question

How to differentiate
`f(x)= (5)/(x) +1`

find f'(x) and f'(2) and f'(4)
I know that to differentiate you do

`\lim_(changex \to 0) (f(x+changex)-f(x))/(changex)` where changex=Δx
but I'm stuck
ples help

Answer 1

`f(x) = (5)/(x) =5x^-^1`


`f'(x)= -5x^-^2= (-5)/(x^2)`


`\text{plug in x = 2 and x=4}`


`f'(2)= (-5)/(2^2) = 2^2 = 4 = (-5)/(4)`


`f'(4)= (-5)/(4^2) = 4^2 = 4*4 = 16 = (-5)/(16)`


`\text{Hence solved }`