The Eigenvalues of the Matrix $A = \left( \begin{array} { c c } 1 & - 2 \\1 & 4\end{array} \right)$

question 15

Multiple Choice

The eigenvalues of the matrix $A = \left( \begin{array} { c c } 1 & - 2 \\1 & 4\end{array} \right)$ are

• A) \(( 5 \pm \sqrt { 17 } ) / 2\)
• B) \(( - 5 \pm \sqrt { 17 } ) / 2\)
• C) 1, 2
• D) 2, 3
• E) 2, 2

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Definitions:

A-not-B Error

A cognitive error observed in infants, where they repeatedly reach for an object at a previous location (A) where it was found, despite seeing it moved to a new location (B).

Hidden Objects

Items that are not easily observable and require effort to be found, often used in games and psychological tests to assess perception and attention.

Incentive

A reward or stimulus that motivates or encourages an individual to perform an action or exhibit a particular behavior.

Familiar Hiding Place

A location where an individual feels safe and chooses to retreat to, typically known only to them or a select few, often used for comfort or security.