Linear algebra(linear transformation)

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The discussion focuses on finding the linear transformation T applied to the vector [4,3]T using the basis B = {[1,1]T,[1,2]T} and the matrix representation [T]B = |1 2| |3 4|. To solve the problem, it is suggested to express [4,3]T as a linear combination of the basis vectors. The matrix product of [T]B and the vector representation is emphasized as the main calculation needed. The importance of understanding that the columns of the transformation matrix represent the images of the basis vectors is highlighted. The discussion concludes with a focus on correctly applying linear combinations to find the final answer.
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Homework Statement


Let B={[1,1]T,[1,2]T} be a basis of R2.
Suppose T\inL(R2,R2) with [T]B=
|1 2|
|3 4|

Homework Equations


Find T([4,3]T)

The Attempt at a Solution


I augmenting matrix A such that [A|[T]B]
 
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Why augmenting? The way you have written that you are just asked to find the matrix product
\begin{bmatrix}1 & 2 \\ 3 & 4\end{bmatrix}\begin{bmatrix}4 \\ 3\end{bmatrix}
 
Remember, the columns in the matrix representation of T are just the image of the basis vectors. That is [T]B =

<br /> \left(\begin{array}{cc} | &amp; | \\ T(v_1) &amp; T(v_2) \\ | &amp; | \end{array}\right)<br />

Use this and then write (4,3) as a linear combination of the basis vectors.
 
then would it be
|1| + |1|
|1|*4 + |2|*3= answer?
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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