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Math Help - Inverse

  1. #1
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    Inverse

    Find the inverse of a nxn matrix defined as:

    a_{ij}=\begin{cases}1, & \text{if} \ \ i\leq j\\0, & \text{if} \ \ i>j\end{cases}

    If A is 2x2, the matrix is \begin{bmatrix}1&-1\\0&1\end{bmatrix}

    If A is 3x3, \begin{bmatrix}1&-1&0\\0&1&-1\\0&0&1\end{bmatrix}

    I am not seeing a recognizable pattern.

    I can see this much

    a^{-1}_{ij}=\begin{cases}1, & \text{if} \ \ i= j\\0, & \text{if} \ \ i>j\\ \text{potential another case here}\end{cases}
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  2. #2
    Master Of Puppets
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    Re: Inverse

    Hey DW, what about this

    a^{-1}_{ij}=\begin{cases}1, & \text{if} \ \ i= j\\-1, & \text{if} \ \ i=j-1\\ \text{0 elsewhere}\end{cases}
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