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13. QR Decomposition (Gram Schmidt Method) example ( Enter your problem )
  1. Example `[[1,-1,4],[1,4,-2],[1,4,2],[1,-1,0]]`
  2. Example `[[3,2,4],[2,0,2],[4,2,3]]`
  3. Example `[[1,-4],[2,3],[2,2]]`
  4. Example `[[1,2,4],[0,0,5],[0,3,6]]`

2. Example `[[3,2,4],[2,0,2],[4,2,3]]`





Find QR Decomposition (Gram Schmidt Method) ...
`[[3,2,4],[2,0,2],[4,2,3]]`


Solution:
Here `A` = 
`3``2``4`
`2``0``2`
`4``2``3`


`q_1'``=a_1` = 
`3`
`2`
`4`
 = 
`3`
`2`
`4`


`r_(11)=||q_1'||=sqrt((3)^2+(2)^2+(4)^2)=sqrt(29)=5.3851648071`

`q_1 = 1/(||q_1'||) * q_1'` = `1/5.3851648071 * `
`3`
`2`
`4`
 = 
`0.5570860145`
`0.3713906764`
`0.7427813527`


`r_(12)=q_1^T * a_2` = 
[`0.5570860145``0.3713906764``0.7427813527`]
 `xx` 
`2`
`0`
`2`
`=2.5997347345`


`q_2'``=a_2-r_(12) * q_1` = 
`2`
`0`
`2`
 `-2.5997347345` 
`0.5570860145`
`0.3713906764`
`0.7427813527`
 = 
`0.5517241379`
`-0.9655172414`
`0.0689655172`


`r_(22)=||q_2'||=sqrt((0.5517241379)^2+(-0.9655172414)^2+(0.0689655172)^2)=sqrt(1.2413793103)=1.1141720291`

`q_2 = 1/(||q_2'||) * q_2'` = `1/1.1141720291 * `
`0.5517241379`
`-0.9655172414`
`0.0689655172`
 = 
`0.4951875685`
`-0.8665782448`
`0.0618984461`


`r_(13)=q_1^T * a_3` = 
[`0.5570860145``0.3713906764``0.7427813527`]
 `xx` 
`4`
`2`
`3`
`=5.199469469`


`r_(23)=q_2^T * a_3` = 
[`0.4951875685``-0.8665782448``0.0618984461`]
 `xx` 
`4`
`2`
`3`
`=0.4332891224`


`q_3'``=a_3-r_(13) * q_1-r_(23) * q_2` = 
`4`
`2`
`3`
 `-5.199469469` 
`0.5570860145`
`0.3713906764`
`0.7427813527`
 `-0.4332891224` 
`0.4951875685`
`-0.8665782448`
`0.0618984461`
 = 
`0.8888888889`
`0.4444444444`
`-0.8888888889`


`r_(33)=||q_3'||=sqrt((0.8888888889)^2+(0.4444444444)^2+(-0.8888888889)^2)=sqrt(1.7777777778)=1.3333333333`

`q_3 = 1/(||q_3'||) * q_3'` = `1/1.3333333333 * `
`0.8888888889`
`0.4444444444`
`-0.8888888889`
 = 
`0.6666666667`
`0.3333333333`
`-0.6666666667`


`Q``=[q_1,q_2,q_3]` = 
`0.5570860145``0.4951875685``0.6666666667`
`0.3713906764``-0.8665782448``0.3333333333`
`0.7427813527``0.0618984461``-0.6666666667`


`R` = 
`r_(11)``r_(12)``r_(13)`
`0``r_(22)``r_(23)`
`0``0``r_(33)`
 = 
`5.3851648071``2.5997347345``5.199469469`
`0``1.1141720291``0.4332891224`
`0``0``1.3333333333`




checking `Q xx R = A?`

`Q xx R` = 
`0.5570860145``0.4951875685``0.6666666667`
`0.3713906764``-0.8665782448``0.3333333333`
`0.7427813527``0.0618984461``-0.6666666667`
 `xx` 
`5.3851648071``2.5997347345``5.199469469`
`0``1.1141720291``0.4332891224`
`0``0``1.3333333333`
 = 
`3``2``4`
`2``0``2`
`4``2``3`


and `A` = 
`3``2``4`
`2``0``2`
`4``2``3`


Solution is possible.




This material is intended as a summary. Use your textbook for detail explanation.
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