How Does Position Vector Calculation Work in Geometry?

In summary, the equations given can be represented by position vectors and used to find the intersection point of two lines. The position vectors for points A, B, C, D, E are represented as a, b, c, d, e respectively. The line between points A and D can be found using the equation a+t*(d-a) and the line between points B and E can be found using b+s*(e-d). By finding the values of t and s that give the same point, the position vector G can be determined, representing the intersection point of the two lines.
  • #1
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AD = AB + 2/3BC
OD - OA = OB - OA + 2/3(OC - OB)
OD = 1/3OB + 2/3OC

BE = BC + 3/4CA
BE = OC - OB + 3/4 OA - 3/4OC
OE = 1/4OC - OB + 3/4OA

Could someone please tell me if I am on the right track with this?
I am also stuck on the finding the position vector G. Whenever I attempt to find it, the G always cancels out leaving me with no equation left.
 
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  • #2
Your doing ok so far. So if you represent each position vector as they suggested, e.g. OA=a, OB=b, OC=c, etc, you've got e=(3/4)a+(1/4)c and d=(1/3)b+(2/3)c, right? The line between A and D is given by a+t*(d-a) where t is a parameter which describes where you are on the line (e.g. if t=0 you are at a and if t=1 you are at d). Similarly the line between B and E is given by b+s*(e-d) for a different parameter s. You want to find the intersection of those two lines. I.e. find values of t and s that give the same point.
 
  • #3


I cannot determine if you are on the right track without more context or information. However, I can provide some general feedback on the equations you have provided.

Firstly, the equations given appear to be position vector equations, which describe the location of a point in space relative to a reference point (usually the origin). These equations are typically used in geometry and physics to describe the position of objects in a coordinate system.

In the first equation, AD = AB + 2/3BC, it is important to note that position vectors are typically written with an arrow on top (e.g. →AD) to indicate that it is a vector quantity. The equation is saying that the position vector for point D is equal to the position vector for point A plus 2/3 of the position vector for point B. This means that point D is located 2/3 of the distance between points A and B.

The second equation, OD - OA = OB - OA + 2/3(OC - OB), is showing that the position vector for point D can also be found by subtracting the position vector for point A from the sum of the position vectors for points B and C. This is a useful property of position vectors, as it allows us to find the position of a point relative to other points in space.

Moving on to the third equation, BE = BC + 3/4CA, it follows the same pattern as the first equation, stating that the position vector for point E is equal to the position vector for point C plus 3/4 of the position vector for point A. Again, this means that point E is located 3/4 of the distance between points C and A.

The last equation, OE = 1/4OC - OB + 3/4OA, is similar to the second equation, showing that the position vector for point E can also be found by subtracting the position vector for point B from the sum of 1/4 of the position vector for point C and 3/4 of the position vector for point A.

As for finding the position vector for point G, it is difficult to provide guidance without more information about the problem you are trying to solve. It could be that the position vector for point G cannot be determined using the given information, or there may be a mistake in the equations provided. It may be helpful to review the problem and any given information to see if there are
 

FAQ: How Does Position Vector Calculation Work in Geometry?

1. What is a position vector?

A position vector is a mathematical representation of a point in space. It is a directed line segment that starts at the origin of a coordinate system and ends at the point in question. It is typically represented by an arrow with its tail at the origin and its head at the point.

2. How is a position vector different from a displacement vector?

A position vector represents the location of a point in space, while a displacement vector represents the change in position of a point. Displacement vectors are typically used to describe the movement of an object from one position to another, while position vectors are used to describe the location of an object at a specific point in time.

3. What is the magnitude of a position vector?

The magnitude of a position vector is the distance between the point it represents and the origin of the coordinate system. It is calculated using the Pythagorean theorem, where the length of the vector is the hypotenuse of a right triangle formed by the x, y, and z components of the vector.

4. How do you find the direction of a position vector?

The direction of a position vector is given by the angle it makes with the positive x-axis in a counterclockwise direction. This angle can be found using trigonometry, specifically the arctangent function, by taking the ratio of the y and x components of the vector.

5. How are position vectors used in geometry?

Position vectors are used in geometry to describe the location of points, lines, and shapes in space. They are also used to calculate distances, angles, and other geometric properties. Additionally, they are used in transformations such as translations and rotations, and in vector operations such as addition and subtraction.

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