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YuhangZhou88 / ESL_Solution

https://yuhangzhou88.github.io/ESL_Solution/
MIT License
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ex 5.11 #8

Open HaiyiS opened 2 years ago

HaiyiS commented 2 years ago

Hello! Can you further explain the formula right below the sentence : "it is easy to show..." . I don't get that. Thank you!

YuhangZhou88 commented 2 years ago

Hello,

By definition of matrix multiplication, if you write it out explitly and notice that the first two rows of matrix Sigma are zero.

HaiyiS commented 2 years ago

Thanks for your reply! But I still don't know how this is working. I can see the omega matrix multiplied by vector X is zero. But in this case there is a matrix N inverse in the middle of omega matrix and vector X.