May be a typo in matrix-calculus tutorial

[baldasan]

Hi Pili,

I really appreciate all the info you shared here. Thanks!
May be you have a type in eq. 50 in hu2012-matrix-calculus.
If I properly understood, this is just the recap and it represents the theorem 6 (eq. 23).
So I guess eq. 50 should have dx instead of x:
$$ df=Tr[A^Tdx] \tag{50}$$
If I'm right also eq 172 in the final Cheat Sheet should be aligned.

Thanks,
Antonio