for ist just use integration b y parts taking 'x' as differentiable function, u will get the ans,
for 2nd use x = (Ï€ + 0 - x), u wil get the ans easily..................
find ∫xdx/(1+sin x) limits 0 to pie/2
find ∫x(tan x)dx/{(sec x)+(tan x)} limits 0 to pie
for ist just use integration b y parts taking 'x' as differentiable function, u will get the ans,
for 2nd use x = (Ï€ + 0 - x), u wil get the ans easily..................