" 21."ln tan x

log tan x

derivative of log tan x

lim_(x rarr0)(log tan2x)/(log tan x)

int((ln(tan x))/(sin x cos x)dxi se q u a lto (a) (1)/(2)ln(tan x)+c(b)(1)/(2)ln(tan^(2)x)+c(c)(1)/(2)(ln(tan x))^(2)+c(d) none of these

If f(x) = log (tan x), then f^(')(x) =

log (sec 2x +tan 2 x)

lf_(log_(2)(3sin x)-log_(2)(cos x)-log_(2)(1-tan x)-log_(2)(1+tan x)=1) then tan x=