# Calc III. Vectors and the Geometry of Space

1. Oct 23, 2007

### perc_wiz11

1. The problem statement, all variables and given/known data
Use vectors to find the points of trisection of the line segment with endpoints (1,2) and (7,5).

2. Relevant equations
Not sure.

3. The attempt at a solution
I don't really know where to start. i tried to create a standard vector equation but its a line segment not a vector.

2. Oct 23, 2007

### Kurdt

Staff Emeritus
If you had two position vectors a and b, then how could you describe the line segment in terms of these vectors? Then what do you imagine the coordinates of position vectors at the trisection points will be?

3. Oct 24, 2007

### perc_wiz11

once i create a standard vector, can say that the points of trisection are at the scalar multiples of v? then translate them back to the line segment at its original position? so if the standard vector is <6,3> and take 1/3 v the points of trisection on that vector are (2,1) and (4,2). once i translate that, would the answer be (3,3) and (5,4) ?

4. Oct 24, 2007

### HallsofIvy

Staff Emeritus
Not without saying what v is!

Is v the vector from (1, 2) to (7, 5)? If so, then what you are doing is correct and you have the right answer.