Core Pure - Linear Transformations Flashcards
What is the new point after a transformation called?
The image
What does a linear transformation mean?
In equations?
All variables in the matrix is in the form ax+by
What is a common mistake in identifying a linear transformation?
X+3 is not a linear transformation
What does a linear transformation always do?
It always maps the origin onto itself
What can all linear transformations be represented as?
A matrix
What is the general form to explain matrices in linear transformations?
What makes this statement true?
What is the notation for a transformed point?
Point S’ has been transformed from point S
Or: look at the image
How can all linear transformations be described?
They can be described on the effect that they have on the unit vectors:
What is the most important thing with 2x2 matrix linear transformations?
What does this infer: T(a+b)
Since T(a+b)=Ta+Tb you can add 2 image vectors to find the 4th vertex after a transformation has been done
When won’t change in a linear transformation?
The origin
What is an invariant point?
points that are mapped onto themselves under the given transformation
What is an invariant line?
lines that each point is mapped back onto the line
They can move along the line so be careful
What is always an invariant point?
The origin
What matrix represents a reflection in the y axis?
(2x2)
When doing a reflection in they y axis, where are the invariant points?
All points on the y axis
When doing a reflection in they y axis, which lines are invariant lines?
X=0 and y=k (for any value of k)
What matrix represents a reflection in the x axis?
When doing a reflection in the x axis, which points are invariant points?
All points on the x axis
When doing a reflection in the x axis, which lines are invariant lines?
The lines: y=0 and x=k (for any value of k)
State the matrices used for a reflection in the x and y axis
What 4 lines do you need to know the matrix for a reflection in?
y and x axis
y=x
y=-x
What matrix represents the reflection in the line y=x?
When doing a reflection in the line y=x, what are the invariant points?
Points on the line y=x
When doing a reflection in the line y=x, what are the invariant lines?
The lines y=x and y=-x+k (for any value of k) are invariant lines
What matrix represents the reflection in the line y=-x?
When doing a reflection in the line y=-x, what are the invariant points?
Points on the line y=-x are invariant points
When doing a reflection in the line y=-x, what are the invariant lines?
The lines y=-x and y=x+k (for any value of k) are invariant lines