how to evaluate symbolic functions in matlab?

Example I have x=[1,1]; how can I evaluate Displacement1 by value x? Note: in my problem x can be varied to x(n). I try to use command 'subs', but it is not convenient because I have to change every time when x varied to x(n). thank you very much for all your commends.

Displacement1 = [ 0, -(9*x(2) + 18*2^(1/2)*x(1))/(25*x(1)*x(2)), 0]

[Walter Roberson]

Could you give an example of when x should be varied to x(n) ?

[Chan Heng]

Example:

 Displacement1=[0, (4*L*P*x(1)*x(2)*x(3)*x(4)*x(5) + L*P*x(1)*x(4)*x(5)*x(6) + 2*L*P*x(2)*x(4)*x(5)*x(6) + 2*2^(1/2)*L*P*x(1)*x(2)*x(4)*x(6) + 2*2^(1/2)*L*P*x(1)*x(2)*x(5)*x(6))/(Ee*x(1)*x(2)*x(4)*x(5)*x(6)), 0]

in here I have n=6,so we want to evaluate the function Displacement1 by value x=[1,1,1,1,1,1]. thank you very much for your comment.