0Still learning
Know0
What is a transformation matrix?
Enjoying Flashcards?
Tell us what you think
What is a transformation matrix?
A transformation matrix is a matrix that is used to determine the coordinates of an image from the transformation of an object.
How is a shape on a plane represented by a matrix?
A shape on a plane can be written as position matrix , where is the coordinate pair of a point on the shape.
What is the formula for finding the coordinates of an image under a transformation?
The formula for finding the coordinates of an image under a transformation is
Where:
represents the coordinates of any point in the 2D plane
represents the coordinates of the image of point
and are given matrices
How are the coordinates of an original point found from the coordinates of the image of the point and the transformation matrix?
To find the original points given the image points, the equation can be rearranged to .
You need to find the inverse transformation matrix.
True or False?
The matrix represents a clockwise rotation, through an angle of , about the point .
False.
The matrix does not represent a clockwise rotation, through an angle of , about the point , it represents a counter-clockwise rotation.
The matrix represents a clockwise rotation, through an angle of , about the point .
These matrices are both given in your exam formula booklet.
What matrix represents a reflection in the line ?
The matrix represents a reflection in the line .
This matrix is given in your exam formula booklet.
What transformation does the matrix represent?
The matrix represents an enlargement with scale factor with centre .
This matrix is given in your exam formula booklet.
True or False?
The matrix represents a translation, of units in the x-direction and units in the y-direction.
True.
The matrix represents a translation, of units in the x-direction and units in the y-direction.
This matrix is not given in your exam formula booklet.
What matrix represents a vertical stretch (stretch parallel to the y-axis) with scale factor ?
The matrix represents a vertical stretch (stretch parallel to the y-axis) with scale factor .
This matrix is given in your exam formula booklet.
What transformation does the matrix represent?
The matrix represents a horizontal stretch (stretch parallel to the x-axis) with scale factor with centre .
This matrix is given in your exam formula booklet.
True or False?
A single matrix representing a composite transformation can be found by multiplying together individual transformation matrices.
True.
A single matrix representing a composite transformation can be found by multiplying together individual transformation matrices.
If the transformation represented by matrix is applied first, followed by another transformation represented by matrix , then the composite matrix is .
Given a transformation represented by the matrix , what does represent?
would be the matrix for five applications of the transformation .
What does the determinant of a transformation matrix represent?
The absolute value of the determinant of a transformation matrix is the area scale factor.
Area scale factor = .
How can the determinant of a transformation matrix be used to find the area of an image?
As the determinant of a transformation matrix is the area scale factor, the product of the area of the original object and the determinant of the transformation matrix will give the area of the image.
Area of image = × Area of object
What will happen to the area of the image if the absolute value of the determinant of the transformation matrix is less than 1.
If the absolute value of the determinant of the transformation matrix is less than 1, then the area of the image will reduce.
What will happen to the orientation of the image if the determinant of the transformation matrix is less than 0.
If the determinant of the transformation matrix is less than 0, then the orientation of the shape will be reversed.
I.e. the shape is reflected.