# Math Help - Derivatives of Matrices

1. ## Derivatives of Matrices

Hi everybody,

I have attached the problem I encountered. --> Estimation of a parameter theta trough minimizing the sum of squares.
How to get the derivative of this matrices and solve for theta?

Thank you very much for any help or references.

2. ## Re: Derivatives of Matrices

Use the product rule treating the matrices as constants:
$\left[\left(X- A\theta\right)^t\left(X- A\theta\right)\right]'= (-A)^t(X- A\theta)- (X- A\theta)^t\A$

3. ## Re: Derivatives of Matrices

Thank you very much!

Now, I got the end result which I attached below!

But how to get there from the derivative above?

(I would also be happy about any online resources on how to manipulate such Matrix operations...)

Here's the end result: