Divide a specific element in a matrix

For example I have:

A=[1 2 3; 3 2 4; 5 4 1]

And I want it like this:

A=[1 -2 -3; -3 2 -4; -5 -4 1]

As you can see i'm trying to divide A12 A13 A21 A23 A31 A32 by -1, how can I do it?

Thank you

[James Tursa]

From your description, wouldn't the result be this instead?

A = [1 -2 -3; -3 2 -4; -5 -4 1]

If not, then what is the rule?

[Tran Thien]

Yes it is, sorry i'll edit it :D

Answer 1

[Fangjun Jiang]

A.*(2*eye(3)-1)

[Tran Thien]

Thank you ! I did it :D