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Let `p` be a non singular matrix, and `I + P + p^2 + ... + p^n = 0,` then find `p^-1`. |
Answer» We have, `I+p++p^(2)+...+p^(n)=O` ...(1) Since p is non-sigular matrix, p is invertible. Multiplying both sides of (1) by `p^(-1)`, we get `implies =^(-1)I+p^(-1)p+p^(-1)p^(2)+...+p^(-1) p^(n)=p^(-1)O` `implies p^(-1)+I+p+p^(2)+...+p^(n-1)=O` `implies p^(-1)=-(I+p+p^(2)+...+p^(n-1))` `implies p^(-1)=- (-p^(n))=p^(n)` |
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