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a 1
1 -a
i find the inverse, which is
a/(a^2 + 1) 1/(a^2 + 1)
1/(a^2 + 1) -a/(a^2 + 1)
which is correct, no?
so can i multiply that matrix byand get this matrix
a 1
1 -a
which is the same as the initial matrix? so is it true that that matrix is its own inverse?
Sorry guys but i cant seem to work out how to do matrices in here properly
Just checking I'm following what you're after: if you call your original matrix A, and your inverse is A^-1, you want A^-1A = I?
If so, your inverse is
-a/(-a^2 - 1) -1/(-a^2 - 1)
-1/(-a^2 - 1) a/(-a^2 - 1)
If your original matrix was its own inverse, then AA=I, but in your case AA =
a^2 + 1 0
0 1 + a^2
Which is (a^2 + 1)I, but not I itself.
yeah thats right...thanks heaps mate
i think ive worked out what i need to know now, thanks heaps