Warning: Matrix is singular to working precision. HELP

This is my code :

sina=4/sqrt(4^2+5^2);
cosa=5/sqrt(4^2+5^2);
sinb=2/sqrt(2^2+5^2);
cosb=5/sqrt(2^2+5^2);
A=zeros(15:15);
A(1,1)=-1; A(1,13)=-cosa
A(2,9)=-1; A(2,13)=-sina
A(3,1)=1; A(3,2)=-1; A(3,14)=-cosa;
A(4,10)=-1; A(4,13)=-sina;
A(5,2)=1; A(5,3)=-cosb
A(6,3)=-sinb; A(6,11)=-1;
A(7,3)=cosb; A(7,4)=-cosb; A(7,15)=cosb;
A(8,3)=sinb; A(8,4)=-sinb; A(8,12)=-1; A(8,15)=-sinb;
A(9,5)=-1;
A(10,5)=1; A(10,6)=-1; A(10,13)=cosa;
A(11,10)=1; A(11,13)=sina;
A(12,7)=1; A(12,8)=-1;
A(13,12)=1;
A(14,4)=cosb; A(14,8)=1;
A(15,4)=sinb;

I get matrix A, but when I wrote this:

alfa=A^-1;

Matlab gives me error

I added some photos

Answer 1

[madhan ravi]

See https://www.mathworks.com/help/matlab/ref/pinv.html#mw_ffa95973-29a2-48a1-adb0-5a4214e0d9cf

det(A) % is zero therefore the matrix is singular so the inverse does not exist

Try using

pinv(A)