Question

seja f(x)= 1+x
____
1- x . A derivada calculada para x= 1/3?

Answer 1

$\frac{1+x}{1-x} \\ \\ \frac{(1+x)'(1-x)-(1+x)(1-x)'}{ (1-x)^{2} } \\ \\ \frac{1(1-x)-(1+x)(-1)}{(1-x)^2} \\ \\ \frac{1-x-(-1-x)}{ (1-x)^{2} } \\ \\ \frac{1-x+1+x}{(1-x)^2} \\ \\ \frac{2}{(1-x)^2} \\ \\ \\ \\ \frac{2}{(1- \frac{1}{3})^2 } \\ \\ \frac{2}{ (\frac{2}{3})^2} \\ \\ \frac{2}{ \frac{4}{9} } \\ \\ \frac{9.2}{4} \\ \\ \frac{18}{4} = \frac{9}{2}$