find out dependent variables from an expression

syms x(t)
y=x^2+2;
symvar(y)

It gives the ans as t.

Desired output is x. How to get the desired output.

Thanks in advance

Answer 1

[Walter Roberson]

syms x(t)
y=x^2+2;
findSymType(y, 'symfun')

ans = 

[Arpan Laha]

That works. Thanks

Answer 2

[Cris LaPierre]

syms x
y=x^2+2;
symvar(y)

ans = 

x

[Arpan Laha]

I have my functions in x(t) form only.

[Cris LaPierre]

Then the symvar is t, as you see. symvar returns symbolic variables in an expression. As you have set it up, x and y are symbolic functions, not variables. t is the only symbolic variable.