Jawapan

2015-03-09T23:40:34+08:00
Tan x = sin x/cos x
then kita guna substituition 
u= cos x 
cari 
du = -sin x dx
integrate (sin x/cos x)dx = - integrate (-1)sin x dx/cos x 
substitute du dan u
=-integrate du/u
selesaikan 
>-ln |u| + C
substitue u dgn cos x
>-ln |cos x| + C