Implicit Function Theorem Tricky Proof on matrices?

In summary, using the Implicit Function Theorem, we can show that an n x n matrix B can be solved for as a continuous differentiable function of a matrix A when || A - id || is sufficiently small, from the equation BAB = id. This is done by defining F(A,B) = BAB - id and using the theorem to find an implicit function B = f(A) that satisfies the equation. Therefore, the proof for this problem involves using the Implicit Function Theorem and showing that B = f(A) is a continuous differentiable function of A.
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Implicit Function Theorem ...Tricky Proof on matrices!?

Homework Statement



Implicit Function Theorem ... Tricky Proof on matrices!?
Show with the Implicit Function Theorem, that an n x n matrix B, can be solved for as a continuous differentiable function of a matrix A (which is n x n), from the equation BAB = id, given that || A - id || is sufficiently small.

Can someone outline the solution to this problem? I don't know how to proceed with the proof.

Can you please show all the steps of the proof?
 
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Homework Equations BAB = id|| A - id || is sufficiently smallThe Attempt at a Solution Let B(A) be a continuous differentiable function of A.We want to show that B can be solved for from the equation BAB = id when || A - id || is sufficiently small. We will use the Implicit Function Theorem for this. The Implicit Function Theorem states that if we have an equation of the form F(X,Y) = 0 and F is differentiable with respect to Y then there is an implicit function Y = f(X) such that F(X,Y) = 0. In our case, we have an equation BAB = id. Let F(A,B) = BAB - id. Then F is differentiable with respect to B. By the Implicit Function Theorem, there is an implicit function B = f(A) such that BAB = id. Now since || A - id || is sufficiently small, we can conclude that B = f(A) is a continuous differentiable function of A and that B can be solved for from the equation BAB = id when || A - id || is sufficiently small.
 

1. What is the Implicit Function Theorem and how is it used?

The Implicit Function Theorem is a mathematical tool used to find solutions to equations that are not explicitly solved for a specific variable. It allows us to find relationships between variables without having to solve for one of them explicitly.

2. What makes the proof of the Implicit Function Theorem on matrices tricky?

The proof of the Implicit Function Theorem on matrices involves manipulating a system of equations involving matrices, which can be more complex and challenging than working with scalar equations. It also requires a thorough understanding of linear algebra and matrix operations.

3. Can the Implicit Function Theorem be applied to any type of matrix equation?

Yes, the Implicit Function Theorem can be applied to any system of equations involving matrices, as long as certain conditions are met. These conditions include the matrices being square and invertible, and the equations being continuously differentiable.

4. How does the Implicit Function Theorem relate to other theorems in mathematics?

The Implicit Function Theorem is closely related to several other theorems in mathematics, including the Inverse Function Theorem and the Implicit Function Theorem for single-variable functions. It is also used in the proof of the Rank-Nullity Theorem in linear algebra.

5. What are some real-world applications of the Implicit Function Theorem on matrices?

The Implicit Function Theorem on matrices has various applications in fields such as physics, economics, and engineering. It is used to study systems of differential equations, to model and analyze economic systems, and to solve optimization problems in engineering designs.

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