is there a 2x2 matrix A so A2 = -I?

Linear spaces and subspaces, linear transformations, bases, etc.
king&i
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is there a 2x2 matrix A so A2 = -I?

Postby king&i » Wed Sep 09, 2009 7:22 pm

is there a 2x2 matrix A so A2 = -I?
(I is ident matrix)

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stapel_eliz
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Postby stapel_eliz » Wed Sep 09, 2009 9:20 pm

Hint: Try a 2-by-2 matrix with zeroes on the diagonal:

. . . . .

See where this leads.... :wink:

nona.m.nona
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Re: is there a 2x2 matrix A so A2 = -I?

Postby nona.m.nona » Thu Sep 17, 2009 6:42 pm

In case you're still working on this:




Now solve. There is more than one solution.


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