Is A^0 Equal to the Zero Matrix O_m,n?

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Homework Statement



state if the statement if it's true or false (give a brief explanation if it's true or give a counter example if it's false)

Homework Equations


If A is an invertible nxn matrix, then A^m is not equals to O_m,n for all natural m


The Attempt at a Solution


what is O_m,n?
 
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I presume it would be the zero matrix (the unique m x n matrix all whose entries are 0).
 
In other words, if A is an invertible matrix, is it possible to have A^n= 0 for some n? Start multiplying both sides of A^n= 0 by A^{-n}. "Repeat as needed".
 
I would choose another approach, where the hint "consider the determinant" applies.

Take your pick :)
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...

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