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tkhunny Group TitleBest ResponseYou've already chosen the best response.0
Are you OK with what a 3x3 matrix is?
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
do you want a formal definition or a solved example showing all steps of inverting a 3x3 matrix?
 one year ago

LOOSEr Group TitleBest ResponseYou've already chosen the best response.0
a solved example would be great
 one year ago

LOOSEr Group TitleBest ResponseYou've already chosen the best response.0
@mathsmind ???
 one year ago

LOOSEr Group TitleBest ResponseYou've already chosen the best response.0
which means its determinant cant be 0?
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
yest i will show you the full steps
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
consider the following matrix
 one year ago

LOOSEr Group TitleBest ResponseYou've already chosen the best response.0
PLZ continue
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
\[A=\left[\begin{matrix}1 & 2 & 0\\ 3& 1 & 5\\ 1 & 2 & 3\end{matrix}\right]\]
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
Step one: \[A^T\]
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
which means transpose of rows and columns of A
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
\[A^T=\left[\begin{matrix}1 & 3 & 1\\ 2& 1 & 2\\ 0 & 5 & 3\end{matrix}\right]\]
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
Step Two: find the adjoint or adjugate of A, which implies that we replace each element by their cofactor...
 one year ago

LOOSEr Group TitleBest ResponseYou've already chosen the best response.0
If P = \begin{bmatrix} a &b &c \\ d &e &f \\ g &h &i \end{bmatrix}
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
now please concentrate on this step it is simple but requires a bit of accuracy
 one year ago

LOOSEr Group TitleBest ResponseYou've already chosen the best response.0
And P^4=2P how can we find P
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
let's finish this first part then i will come to the 2nd question, you asked me first for a numerical example
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
so we need to find adjA
 one year ago

LOOSEr Group TitleBest ResponseYou've already chosen the best response.0
I know how to find a inverse matrix. So, can u plz do the 2nd question
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
yes sorry am on the phone, but just a quick hint for P^n we use the principle of induction
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
i will show you shortly
 one year ago

LOOSEr Group TitleBest ResponseYou've already chosen the best response.0
@mathsmind ???
 one year ago

LOOSEr Group TitleBest ResponseYou've already chosen the best response.0
@mathsmind why is taking so long?
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
sorry back, am at work
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
now P^4 means you are multiplying your matrix by itself 4 times.
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
you know how to multiply the, it would be PP=P^2, then P^2P=P^3. then P^3P=P^4
 one year ago

LOOSEr Group TitleBest ResponseYou've already chosen the best response.0
But it would be really long
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
well this is the world of Matrices...
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
are you thinking of algebraic operation on matrices such as taking the inverse of 2P
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
or subtracting p^42P=0 in order to find the new P?
 one year ago

LOOSEr Group TitleBest ResponseYou've already chosen the best response.0
Isn't there any short way
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
have you done hermitian matrices...
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
listen can we kindly finish this tonight because it is 5 am and i need to go ...
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
i will provide you with full solution even if you are not online ok
 one year ago

mathsmind Group TitleBest ResponseYou've already chosen the best response.0
see ya tonight
 one year ago

LOOSEr Group TitleBest ResponseYou've already chosen the best response.0
@ParthKohli
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.0
lol, you still here? I thought you got help
 one year ago

LOOSEr Group TitleBest ResponseYou've already chosen the best response.0
can u do it?
 one year ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
I haven't done matrices yet: I am stuck with number theory at the moment.
 one year ago

yummydum Group TitleBest ResponseYou've already chosen the best response.0
http://www.wikihow.com/Inversea3X3Matrix
 one year ago

sauravshakya Group TitleBest ResponseYou've already chosen the best response.1
@looser there are many matrices such that P^4=2P but only one is invertible which is dw:1361026643638:dw
 one year ago
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