All Calculus 3 Resources
Example Questions
Example Question #11 : Equations Of Lines And Planes
Find the unit tangent vector to the curve given by
To find the unit tangent vector for a given curve, we must find the derivative of each of the components of the curve, and then divide this vector - the tangent vector - by the magnitude of the tangent vector itself.
To start, let's find the derivatives:
The derivatives were found using the following rules:
,
Next, we must find the magnitude of the tangent vector, by taking the square root of the sum of the squares the x, y, and z components. Note that the vector we were given was in unit vector notation, and i, j, and k are each equal to one unit, so they don't impact the magnitude of the vector (they simply indicate direction).
Finally, divide the vector by its magnitude:
Example Question #11 : Equations Of Lines And Planes
Find the unit tangent vector to the given curve:
To find the unit tangent vector for a given curve, we must find the derivative of each of the components of the curve, and then divide this vector - the tangent vector - by the magnitude of the tangent vector itself.
To start, let's find the derivatives:
The derivatives were found using the following rules:
, ,
Next, we must find the magnitude of the tangent vector, by taking the square root of the sum of the squares the x, y, and z components. Note that the vector we were given was in unit vector notation, and i, j, and k are each equal to one unit, so they don't impact the magnitude of the vector (they simply indicate direction).
Finally, divide the tangent vector by its magnitude:
Example Question #13 : 3 Dimensional Space
Find the unit tangent vector given by the curve
To find the unit tangent vector for a given curve, we must find the derivative of each of the components of the curve, and then divide this vector - the tangent vector - by the magnitude of the tangent vector itself.
To start, let's find the derivatives:
We used the following rules to find them:
, ,
Next, we must find the magnitude of the tangent vector, by taking the square root of the sum of the squares the x, y, and z components. Note that the vector we were given was in unit vector notation, and i, j, and k are each equal to one unit, so they don't impact the magnitude of the vector (they simply indicate direction).
Finally, divide the tangent vector by its magnitude:
Example Question #131 : Calculus 3
Write the equation of the line - in vector form - passing through the two points
To find the equation of the line, we first must find the vector passing between the two points:
This was found by .
Next, we pick one point, and using the formula
we get our line:
Example Question #11 : Equations Of Lines And Planes
Write the equation for the plane containing the points
To find the equation of the plane, we need a point on the plane, and the normal vector to the plane, which is given by the cross product of two vectors in the plane.
To start, let's find these vectors:
We found them by subtracting the terminal point (B, C) and the initial point (A, B, respectively).
Now, we can write the determinant in order to take the cross product of the two vectors:
where i, j, and k are the unit vectors corresponding to the x, y, and z direction respectively.
Next, we take the cross product. One can do this by multiplying across from the top left to the lower right, and continuing downward, and then subtracting the terms multiplied from top right to the bottom left:
The equation of a plane is given by
, where is the normal vector and is any point on the plane.
Using our normal vector and the point , we get the equation
Example Question #131 : Calculus 3
Find the equation of the plane given by the three points
To find the equation of the plane given by three points, we need the normal vector to the plane and a point on the plane.
We first must find two vectors on the plane:
These were found by taking the difference between the first and second, and second and third points respectively.
Now, we can write the determinant in order to take the cross product of the two vectors:
where i, j, and k are the unit vectors corresponding to the x, y, and z direction respectively.
Next, we take the cross product. One can do this by multiplying across from the top left to the lower right, and continuing downward, and then subtracting the terms multiplied from top right to the bottom left:
Now, we plug this, and a point of our choosing, into the equation for a plane:
, where is the normal vector and is any given point.
Plugging this in, we get
Example Question #131 : Calculus 3
Find the equation of the plane that contains the point , and has a normal vector .
Using the formula for a plane , where the point given is and the normal vector is . Plugging in the known values, you get . Manipulating this equation through algebra gives you the answer
Example Question #132 : Calculus 3
Write the equation of the plane given by the three points
To find the equation of a plane, we need a point on the plane and the normal vector to the plane.
First, we must find two vectors on the plane using the given points (taking the difference between the two points in each vector):
Now, we can write the determinant in order to take the cross product of the two vectors:
where i, j, and k are the unit vectors corresponding to the x, y, and z direction respectively.
Next, we take the cross product. One can do this by multiplying across from the top left to the lower right, and continuing downward, and then subtracting the terms multiplied from top right to the bottom left:
Now, we choose a point (for example, ) and use the normal vector given by from the cross product:
Plugging all of this in, and simplifying, we get
Example Question #133 : Calculus 3
Find the equation of the plane that contains the point and has a normal vector .
The formula of a plane containing a point and with a normal vector is
,
Using what we were given, we get
.
Through algebra, we get
.
Example Question #134 : Calculus 3
Find the equation of the plane that contains the point and has a normal vector .
Using the formula for a plane, we have
,
where the point given is and the normal vector is .
Plugging in the known values, you get
.
Manipulating this equation through algebra gives you the answer