00:01
So in this question, we say we want to find a parametric equation for the line that passes through the point 214, that is perpendicular to the plane 3x plus y plus z equals 3.
00:20
So let's figure out the normal vector to this plane.
00:26
So the normal vector to this plane is going to be the vector that has, as its components, the coefficients of x, y, and z.
00:39
So 3, 1, and 1, that is my normal vector to that plane.
00:46
And so if we are perpendicular to that plane, we are in the direction of that normal vector to the plane.
00:55
And so now i can write my parametric equations for this line.
01:01
My x, y, and z, each star, at 2, 1, and four respectively.
01:10
And to that, i add my x, y, and z components of the normal vector.
01:16
So my x is equal to 2 plus 3t, my y is equal to 1 plus t, and my z is equal to 4 plus t.
01:26
And that would be my answer to this first question.
01:31
In the second question, we want to find an equation of the plane that contains the line, in r of t, which has components t, 2t, and 3t, as well as the points negative 1, 4, and 1.
01:47
So in order to write the equation of this plane, i'm going to need two vectors that lie in this plane.
01:55
So first of all, consider r0.
01:59
R of 0 would be 0 -0, and so 0 -0 is a point that lies in this plane.
02:08
And so one vector that is going to lie in this plane is going to extend from the point negative 1 -4 -1 to the point 0 -0.
02:24
Such a vector does what? well, if it's going from negative 1 to 0, we're going up 1 in the x direction.
02:33
I'm going down 4 in the y direction.
02:36
If i start at y equals 4 and end at y equals 0, and negative 1 in the z direction, if i start at z equals 1 and i end at z equals 0...