Let
f(x)=1x2\displaystyle {f{{\left({x}\right)}}}={\frac{{{1}}}{{{x}-{2}}}}
Use the limit definition of the derivative to find
(i) f(1)=\displaystyle {f}'{\left(-{1}\right)}=  
(ii) f(1)=\displaystyle {f}'{\left({1}\right)}=  
(iii) f(3)=\displaystyle {f}'{\left({3}\right)}=  
(iv) f(5)=\displaystyle {f}'{\left({5}\right)}=  

To avoid calculating four separate limits, I suggest that you evaluate the derivative at the point when x=a\displaystyle {x}={a}. Once you have the derivative, you can just plug in those four values for "a" to get the answers.