Help wanted

Please post a solution for :
∫(sin3x/x) dx
It is not a non-integratable function so keep trying.

Another teaser

<>i'm sorry for the delay in posting a new message, could'nt find a worthy one

U2 has a concert that starts in just 17 minutes and all of the band members must all cross a bridge to get there. The four men begin on the same side of the bridge and you must help them to get across to the other side.

Due the age of the bridge, only two people can cross at one time. To make matters worse, it is night-time and there is only one torch. The torch is always required when crossing the bridge and the torch must be walked back and forth, it cannot be thrown, etc. Each band member walks at a different speed and a pair must walk together at the rate of the slower man:

Bono takes 1 minute to cross
Edge takes 2 minutes to cross
Adam takes 5 minutes to cross
Larry takes 10 minutes to cross

For example, if Bono and Larry walk across first, it takes them 10 minutes to cross. If Adam then returns with the torch , a total of 15 minutes will have passed. There is no trick behind this, it is the simple movement of resources in the appropriate order

Brain Teasers

The son of a rich bullion merchant left home on the death of his father. All he had with him was a gold chain that consisted of 118 links. He rented a place in the city center with a shop at the lower level and an apartment at the upper level. He was required to pay every week one link of the gold chain as rent for the place.

The landlady told him that she wanted one link of the gold chain at the end of one week, two gold links at the end of two weeks, three gold links at the end of three weeks and so on.

The son realized that he had to cut the links of the gold chain to pay the weekly rent. If the son wished to rent the place for 118 weeks, what would be the minimum number of links he would need to cut?

Integrate if you can

This integral has always troubled mathematicians even my maths teacher couldn't do it.
So if you can solve it consider yourself to be in the league of aryabhatta and ramanujan.

Integrate log(1 + tan x)dx