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Useful identity for determinant in 5.5 #701

Closed rparac closed 2 years ago

rparac commented 2 years ago

Describe the mistake A clear and concise description of what the mistake is.

The formula presented seems incorrect. Trying to apply it on d det(xx^t) dx, x is element of R^2, requires computing a matrix which is not square. This is because the inverse is of shape 2x2, while the dxx^tdx is of shape (2 x 2) x 2, resulting in a 1 x 2 matrix when multiplied.

Location Please provide the

  1. version (bottom of page) Draft (2021-07-29)
  2. Chapter 5.5
  3. page 158
  4. line number/equation number (5.101)

Proposed solution A clear and concise description of what you would like to change.

The trace should be replaced by the transpose, but please double check this.

Additional context Add any other context about the problem here.