How to Mathematically describe a plane?

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In summary, the equation of a plane in three-dimensional space is Ax + By + Cz + D = 0, where A, B, and C are the coefficients of the x, y, and z variables respectively, and D is a constant term. The normal vector of a plane is a vector that is perpendicular to the plane, represented as <b>n</b> = (A, B, C). A plane can be described using two points and a normal vector, with the two points determining the direction and the normal vector providing information about the orientation. To determine if a point (x,y,z) lies on a plane, you can substitute the values into the plane's equation and check if the resulting equation is satisfied
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HMPARTICLE
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The linear combinations of V = (1,1,0) and W = (0,1,1) fill a plane.
My question is how do i describe that plane? (not geometrically).
 
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This plane is the set { s(1,1,0)+t(0,1,1): s,t Reals}={(s, s+t, t)} . Is that what you are looking for?
 
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  • #3
Yes! I understand what the question is asking now! I'm making that transition between A-level and UG.

Thanks WWGD.
 
  • #4
Notice that the cross product is <1, 1, 0> and <0, 1, 1> is <1, -1, 1> and, since this plane contains the origin, it could also be described by the single equation x- y+ z= 0.
 
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To mathematically describe a plane, we can use the equation of a plane in vector form:

r = r0 + sv + tw

where r is a position vector on the plane, r0 is a fixed point on the plane, v and w are two non-parallel vectors that span the plane, and s and t are any real numbers.

In this case, the vectors V = (1,1,0) and W = (0,1,1) are non-parallel and span the plane. So, we can use them to describe the plane as:

r = r0 + s(1,1,0) + t(0,1,1)

To find the fixed point r0, we can choose any point on the plane and substitute its coordinates into the equation. For example, if we choose the point (1,1,0), we get:

(1,1,0) = r0 + s(1,1,0) + t(0,1,1)

Since s and t can be any real numbers, we can choose them to be 0, which gives us:

r0 = (1,1,0)

So, the equation of the plane can be written as:

r = (1,1,0) + s(1,1,0) + t(0,1,1)

This equation can also be written in component form as:

x = 1 + s + t
y = 1 + s
z = t

This is the mathematical description of the plane formed by the linear combinations of V and W. It represents all the points on the plane in terms of two parameters, s and t, which can take on any real values.
 

FAQ: How to Mathematically describe a plane?

What is the equation of a plane in three-dimensional space?

The equation of a plane in three-dimensional space is Ax + By + Cz + D = 0, where A, B, and C are the coefficients of the x, y, and z variables respectively, and D is a constant term.

How do you find the normal vector of a plane?

The normal vector of a plane is a vector that is perpendicular to the plane. To find the normal vector, you can use the coefficients of the x, y, and z variables from the plane's equation. The normal vector is represented as n = (A, B, C).

Can a plane be described using two points and a normal vector?

Yes, a plane can be described using two points and a normal vector. The two points can be used to determine the direction of the plane, while the normal vector provides information about the orientation of the plane.

How do you determine if a point lies on a plane?

To determine if a point (x,y,z) lies on a plane, you can substitute the values of x, y, and z into the plane's equation. If the resulting equation is satisfied, then the point lies on the plane.

What is the distance from a point to a plane?

The distance from a point (x0,y0,z0) to a plane Ax + By + Cz + D = 0 is given by the formula d = |(Ax0 + By0 + Cz0 + D)|/√(A^2 + B^2 + C^2).

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