Solve differential Equation for certain values of variable x

I have to find 4 values of z corresponding to x. After calculating differential equation how can I substitute x in the z(differential) equation? I have attached simplified code so that reader can understand.

x=[2 3 4 5];
syms x
z=diff(sin(x)-cos(x))

Answer 1

[Birdman]

Try this:

syms x
z(x)=diff(sin(x)-cos(x))
xVal=[2 3 4 5];
zVal=z(xVal)

What you need to do is to define a symbolic function z(x) and basically pass numeric values to that function as above. Really simple.

[Iqbal Farjad]

Thanks alot. it works. Sometimes I would make simple things complex.