Show by direct expansion that [tex]| \lambda | ^2 =1 [/tex](adsbygoogle = window.adsbygoogle || []).push({});

For simplicity, take [tex]\lambda[/tex] to be a two-dimensional transformation matrix.

from what I understand, if X was a vector (2,3,4), [tex]| X | [/tex] is finding the length of the vector by adding the square of the numbers and taking a square root. [tex]\sqrt{2^2+3^2+4^2}[/tex]

What I dont understand is how to apply this to a matrix

because a 2x2 matrix times itself is still a 2x2 matrix, and even after one square root's it, it's still a 2x2 matrix, never just 1.

What am I missing?

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# Homework Help: Transformation matrix question

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