Dofficulty in understanding the problem


#1

I dont understand how the cuts are made. int the problem description it says that

For first cut, the length of rod is 6.
For second cut, the length of sub-rod in which we are making cut is 5(since we already have made a cut at 1).
For third cut, the length of sub-rod in which we are making cut is 4(since we already have made a cut at 2).

if we make the cuts in order as explained than we have 6, 6-1=5, 5-2=3, 3-5=-2(not possible)
so the cost of the third cut should be 3 or am i missing something 

#2

It is considering the cost before cutting the rod.
for first cut it will be same for all does not matter where you cut.


#3

You should not do 5-2. What you are doing is that you are assuming a cut of length 2 is made, but instead a cut is made at the point of x = 2 mark!. Means initially after cutting rod at x = 1. Now the Length of the rod will be 5. And now if we make a cut at original x = 2(Now x = 1 from left, as already 1 length has been cut in the first step). So it will be 5-1 = 4 only.