int(1)/(tan x tan(60-x)*tan(60+x))

int(1)/(Tan x Tan(60^(0)-x)tan(60^(@)+x))dx= (1) (1)/(3)log|sin3x|+cquad (2) 3log|sin3x|+cquad (3) (1)/(2)log|sin3x|+cquad (4) (1)/(3)log|cos3x|+cquad

(iii) Prove that tan x tan(60-x)tan(60+x)=tan3x

tan A+tan(60+A)-tan(60-A)=3tan3A

int(1-tan x)/(1+tan x)dx

int (1+tan x )/(1-tan x)dx

Evaluate int(tan x+tan^(3)x)/(1+tan^(3)x)dx

int(1+tan^(2)x+tan^(4)x+tan^(6)x)dx=

int (1+tan^(2)x + tan^(4)x+tan^6 x)dx=

int e^(x) (1+tan x + tan^(2) x) dx

int (1 + tan^(2) x)/(1 -tan^(2) x) dx =