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MIE 2016/Day 1/Problem 6

Revision as of 20:44, 7 January 2018 by Anishanne (talk | contribs) (Created page with "===Problem 6=== Let <math>A</math> be <math>A=\begin{vmatrix}1&a&-2\\a-2&1&1\\2&-3&1\end{vmatrix}</math> with <math>a\in\mathbb{R}</math>. We know that <math>\text{det}(A^2-2A...")
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Problem 6

Let $A$ be $A=\begin{vmatrix}1&a&-2\\a-2&1&1\\2&-3&1\end{vmatrix}$ with $a\in\mathbb{R}$. We know that $\text{det}(A^2-2A+I)=16$. The sum of the values of $a$ that satisfies this condition is:

(a) $0$

(b) $1$

(c) $2$

(d) $3$

(e) $4$

Note: $\text{det}(X)$ is the determinant of the matrix $X$.


Solution

See Also

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