ToO LaZy ^*
n/a
int[pi/2->0] (1 / 1+ sin@) d@
ok this is what i did...
let t = tan(@/2)
dt/d@ = 1/2(1+t<sup>2</sup>)
d@ = 2dt / (1+t<sup>2</sup>)
when @ = pi/2 , t = 1
when @ = 0 , t = 0
.: int[pi/2->0] (1 / 1+ sin@) d@
= int[1->0] (1 / (1 + 2t/1-t<sup>2</sup>) * 2dt / 1 + t<sup>2</sup>
= 2 * int[1->0] (1 / 1 - t<sup>2</sup> + 2t / (1 - t<sup>2</sup>) * dt / 1 + t<sup>2</sup>
after that...nothing seems to cancel out..
what did i do wrong?
ok this is what i did...
let t = tan(@/2)
dt/d@ = 1/2(1+t<sup>2</sup>)
d@ = 2dt / (1+t<sup>2</sup>)
when @ = pi/2 , t = 1
when @ = 0 , t = 0
.: int[pi/2->0] (1 / 1+ sin@) d@
= int[1->0] (1 / (1 + 2t/1-t<sup>2</sup>) * 2dt / 1 + t<sup>2</sup>
= 2 * int[1->0] (1 / 1 - t<sup>2</sup> + 2t / (1 - t<sup>2</sup>) * dt / 1 + t<sup>2</sup>
after that...nothing seems to cancel out..
what did i do wrong?
