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mml-book / mml-book.github.io

Companion webpage to the book "Mathematics For Machine Learning"
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Misleading part in Example 2.8 (Minus-1 Trick) #635

Closed ZhenghaoXiao32 closed 3 years ago

ZhenghaoXiao32 commented 3 years ago

Describe the mistake In the first line of Example 2.8: "Let us revisit the matrix in (2.49), which is already in REF:" The last word should be "Reduced REF" instead of "REF" given the Minus-one Trick can only be applied on Reduced REF.

Location Please provide the

  1. version (bottom of page) Draft (2021-01-14)
  2. Chapter Chapter 2.3 Solving Systems of Linear Equations
  3. page 33
  4. line number/equation number The first line of Example 2.8

Proposed solution Replace "REF" to "Reduced REF"

Additional context When I was trying to solve the exercises, this line misled me to use the Minus-one Trick on REF and led to wrong solutions.

mpd37 commented 3 years ago

thanks. that's correct. will fix it with the next revision