Assuming A is a 2x2 matrix how many different matricies exist such that A^2=I ?(adsbygoogle = window.adsbygoogle || []).push({});

I am 99% sure the answer is 4 but after putting that down as an answer with supporting evidence I was marked wrong (or atleast not fully correct) so I am stumped as to where to jump and whether or not the grader may ahve just messed up.

**Physics Forums - The Fusion of Science and Community**

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# How many 2x2 matricies equal I?

Loading...

Similar Threads - many matricies equal | Date |
---|---|

B ##AB = I \implies BA = I##, for square matricies ##A,B## | Jun 9, 2017 |

I Angle between two vectors with many dimensions | Feb 3, 2017 |

Systems of equations with many equations, more than 3 | Nov 20, 2013 |

Fair to say there are twice as many square matrices as rectangular? | Apr 10, 2013 |

**Physics Forums - The Fusion of Science and Community**