dear all

how do i do for deletion of some columns? example:

A:=Matrix([[1,2,3],[4,5,6],]);

change to this: A:=Matrix([[1,2],[4,5]]).

i have a Matrix 8*12 and i want change it to 8*8

plz help me.

daer all

how can i calculate eigenvalue and eigenvectors for a big Matrix?

example Matrix 12*12.

thank you

 @Carl Love @Markiyan Hirnyk 

i have this Matrix: A:=Matrix([[Matrix[[a,b],[c,d]]], [Matrix[[e,f],g,h]] ])

i want this Matrix change to: A:=Matrix([[a,b,e,f],[c,d,g,h]])

help me plz

thank you

dear all

(1-pi*x/2)y[b]-1/3=int(t^4/sqrt((t^2-y[b])^2+y[a]^2),t);

x^2*y[c](1-pi*x/2)-1/3=int(t^4/sqrt((t^2-x^2*y[c])^2+y[a]^2),t);

i want to plot y[a],y[b],y[c] vs x.

plz help me.

thank you 

dear all

how Matrix(2, 2, [a,b,c,d]) change to:

a b

c d  

without [] !