Finding the Inverse of a Linear Transformation

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To find the inverse of the linear transformation defined by the equations y_1=4x_1-5x_2 and y_2=-3x_1+4x_2, one can solve the system for x_1 and x_2. This involves either isolating x_1 in the first equation and substituting it into the second or eliminating one variable by adding the equations with appropriate coefficients. Another effective method is to express the equations in matrix form and multiply both sides by the inverse of the coefficient matrix. Understanding these techniques allows for the successful calculation of the inverse transformation. Mastering these methods is essential for solving similar linear systems.
UrbanXrisis
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how would one find the inverse of the linear transformation:

y_1=4x_1-5x_2
y_2=-3x_1+4x_2

this was never taught in class, could someone give a little advice as how I would do this?

I know the answer has to be in the form of

x_1=ay_1+by_2
x_2=cy_1+dy_2

could someone explain this process?
 
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You're solving the system of equations for x_1 and x_2.


One way to do it would be to solve the first equation for x_1 and then substitute into the second equation.

Another method would be to add the equations together using suitable coefficitents so that one of the x's is eliminated, and then solve for the other.

In principle, this should be no different than dealing with, for example:
9=4x_1-5x_2
7=-3x_1+4x_2
 
Yet another way is to write the equations in matrix form. (Left) Multiply both sides by the inverse of the coefficient matrix.
 
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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