In the ML lecture notes of cs229, I am not able to derive the equation 3 in matrix derivatives. I applied the equation 1 to derive it, considering the product after A as another matrix, I am not getting the sum and am getting only the second term in the sum given as the derivative. How can I use equation 1 to derive this? Thanks in advance.

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  • $\begingroup$ (3) has two terms involving $A$, so you cannot treat $BA^TC$ as a constant matrix and apply (1) $\endgroup$ – gunes May 29 '20 at 10:30
  • $\begingroup$ Oh, yeah, now I see the mistake in my approach. Thanks a lot. Can you maybe hint at how I can proceed to actually derive (3)? $\endgroup$ – ethan_specter May 29 '20 at 10:36