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Buddhayourlord&savoir

Are matrices A and B inverses? Look in comments to see matrices.

  • 8 months ago
  • 8 months ago

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  1. Buddhayourlord&savoir
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    |dw:1375487302704:dw|

    • 8 months ago
  2. itsmylife
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    just multiply them ,if your gona get identity matrix then yes they are inverse else no

    • 8 months ago
  3. itsmylife
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    \[A*A^{-1}=I\]

    • 8 months ago
  4. Buddhayourlord&savoir
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    What do you mean by "identity matrix"

    • 8 months ago
  5. Buddhayourlord&savoir
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    identical?

    • 8 months ago
  6. jdoe0001
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    \(\bf I = \left[ \begin{matrix} 1&0\\ 0&1 \end{matrix}\right]\)

    • 8 months ago
  7. Euler271
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    And for 2x2 matrices only: \[A = \left[\begin{matrix}a & b \\ c & d\end{matrix}\right]\] \[A^{-1} = \frac{ 1 }{ detA } \left[\begin{matrix}d & -b \\ -c & a\end{matrix}\right]\]

    • 8 months ago
  8. itsmylife
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    |dw:1375487630099:dw|

    • 8 months ago
  9. Buddhayourlord&savoir
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    therefore it is not an inverse since its not all the same?

    • 8 months ago
  10. itsmylife
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    |dw:1375487648610:dw|

    • 8 months ago
  11. jdoe0001
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    \( A \times B = \left[ \begin{matrix} 1&0\\ 0&1 \end{matrix}\right] = \textit{I} \implies B = A^{-1}; A = B^{-1}\)

    • 8 months ago
  12. Euler271
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    watch out with that cross symbol ^_^

    • 8 months ago
  13. jdoe0001
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    lol

    • 8 months ago
  14. jdoe0001
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    \(A \cdot B \) :)

    • 8 months ago
  15. Euler271
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    hehe

    • 8 months ago
  16. Buddhayourlord&savoir
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    this isnt explaining anything at all guys :L

    • 8 months ago
  17. Buddhayourlord&savoir
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    i get the equation but how do i know if it is or is not?

    • 8 months ago
  18. jdoe0001
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    well, you have just have to multiply them

    • 8 months ago
  19. Buddhayourlord&savoir
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    Multiply what? AxB as a whole? The numbers in A with each other? Im sorry im feeling pretty hopeless, i just need a more in-depth explanation please ;/

    • 8 months ago
  20. primeralph
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    Yes. Inverses.

    • 8 months ago
  21. Buddhayourlord&savoir
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    5*-7=-35 -18*2=-36 therefore the answer is no? right?

    • 8 months ago
  22. primeralph
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    I just told you they are inverses.

    • 8 months ago
  23. Buddhayourlord&savoir
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    oh, okay.

    • 8 months ago
  24. Buddhayourlord&savoir
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    thanks man

    • 8 months ago
  25. primeralph
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    You're welcome.

    • 8 months ago
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