Vector calculus, + finding parametric equation

In summary, the conversation discusses finding a set of parametric equations for a line in a plane that goes through a point of intersection with a given line and is perpendicular to that line. The solution involves using substitution and the cross-product to find the normal direction vector and using it in the parametric equation of the line. The answer is confirmed by setting the two lines equal to each other and solving for the variables.
  • #1
CaptainOfSmug
13
0

Homework Statement


The line L
L1: x=3+2t, y=2t, z=t
Intersects the plane x+3y-z=-4 at a point P. Find a set of parametric equations for the line in the same plane that goes through P and is perpendicular to L.

Homework Equations


cross-product
r=r0+t(vector) this is to get in parametric form typically

The Attempt at a Solution


Well let's just say first I'm having trouble visually what this question is asking (is there a program where I can graph this type of stuff in 3 space?)

substituting the values of "L" into the plane equation and then solved for "t" which was -1. I then plugged those values into the parametric equations of the line to get the point of intersection P(1,2,-1)

Here is where I get confused and visually a bit shaky. I decided to use the normal direction vector, I'll call it
"n1" from the plane=<1,3,-1> and "n2" from the line =<2,2,1>
I take the cross product with the resultant vector being <-5,3,4>
So I then use the parametric equation which is: L2 => x=1-5t, y=-2+3t, z=-1+4t

I'm think I'm done at this point because now I have to sets of parametric equations. To check my answer I set
L1 and L2 equal to each other, solved for the variables using elimination and found the intersection point to be the same as I found earlier.

I have no idea if I'm right or wrong, any tips would be helpful! Please don't just tell me the answer, I would prefr someone to point out a mistake and let me figure out the rest, after all, I'm taking math to actually grasp it :)

Thanks in advance!
Cheers
 
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  • #2
CaptainOfSmug said:

Homework Statement


The line L
L1: x=3+2t, y=2t, z=t
Intersects the plane x+3y-z=-4 at a point P. Find a set of parametric equations for the line in the same plane that goes through P and is perpendicular to L.

Homework Equations


cross-product
r=r0+t(vector) this is to get in parametric form typically

The Attempt at a Solution


Well let's just say first I'm having trouble visually what this question is asking (is there a program where I can graph this type of stuff in 3 space?)

substituting the values of "L" into the plane equation and then solved for "t" which was -1. I then plugged those values into the parametric equations of the line to get the point of intersection P(1,2,-1)

Here is where I get confused and visually a bit shaky. I decided to use the normal direction vector, I'll call it
"n1" from the plane=<1,3,-1> and "n2" from the line =<2,2,1>
I take the cross product with the resultant vector being <-5,3,4>
So I then use the parametric equation which is: L2 => x=1-5t, y=-2+3t, z=-1+4t

I'm think I'm done at this point because now I have to sets of parametric equations. To check my answer I set
L1 and L2 equal to each other, solved for the variables using elimination and found the intersection point to be the same as I found earlier.

I have no idea if I'm right or wrong, any tips would be helpful! Please don't just tell me the answer, I would prefr someone to point out a mistake and let me figure out the rest, after all, I'm taking math to actually grasp it :)

Thanks in advance!
Cheers

The intersection point is <1,-2,-1> but that's just a typo. Looks ok otherwise.
 

1. What is vector calculus?

Vector calculus is a branch of mathematics that deals with the study of vectors and their properties. It involves the use of vector operations such as addition, subtraction, multiplication, and differentiation to solve problems in fields such as physics, engineering, and economics.

2. How is vector calculus different from traditional calculus?

Vector calculus involves the use of vectors, which are quantities that have both magnitude and direction, whereas traditional calculus deals with scalar quantities. Vector calculus also includes vector operations and concepts such as dot product, cross product, and line integrals, which are not present in traditional calculus.

3. What is a parametric equation?

A parametric equation is a mathematical expression that defines a set of coordinates in terms of one or more parameters. These equations are often used to represent curves or surfaces in three-dimensional space. Each parameter can be varied to produce a different set of coordinates.

4. How do you find a parametric equation for a curve?

To find a parametric equation for a curve, you first need to identify the coordinates of points on the curve. Then, choose a parameter (usually denoted by t) and express each coordinate in terms of t. This will give you a set of equations that describe the coordinates of points on the curve in terms of the parameter t.

5. What are some real-life applications of vector calculus and parametric equations?

Vector calculus and parametric equations are used in a wide range of fields, including physics, engineering, computer graphics, and economics. They are used to model and analyze motion, calculate forces and work, create 3D animations, and optimize systems. For example, vector calculus is used in the study of fluid dynamics and electromagnetism, while parametric equations are used in computer-aided design and robotics.

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