Question #62e23

1 Answer
Oct 3, 2017

(1+tanx)/(1-tanx)=(tan(pi/4)+tanx)/(1-tan(pi/4)tanx)=tan(pi/4+x)

d/dx((1+tanx)/(1-tanx))
=d/dx(tan(pi/4+x))
=sec^2(pi/4+x)