- #1
- 996
- 5
If V is diagonal, it is easy to show:
[itex](V + V^{-1})^{-1} = V(V^2 + I)^{-1}[/itex]
by multiplying both sides by:
[itex](V + V^{-1})[/itex]
But, I'm wondering if there is a way to derive the RHS from the LHS. Since diagonal matrices behave like scalars, I used a scalar analogy:
[itex] (x + 1/x)^{-1} = ((x^2 + 1)/x)^{-1} = x(x^2 + 1)^{-1}[/itex]
But I'd like to show it using matrix terminology. If there is something simple, I'm missing it. Any ideas?
[itex](V + V^{-1})^{-1} = V(V^2 + I)^{-1}[/itex]
by multiplying both sides by:
[itex](V + V^{-1})[/itex]
But, I'm wondering if there is a way to derive the RHS from the LHS. Since diagonal matrices behave like scalars, I used a scalar analogy:
[itex] (x + 1/x)^{-1} = ((x^2 + 1)/x)^{-1} = x(x^2 + 1)^{-1}[/itex]
But I'd like to show it using matrix terminology. If there is something simple, I'm missing it. Any ideas?