I dont know what is wrong ? MATLAB error in 'int'

Question

I am new to MATLAB. I tried to use this command but it gives an error.

Can you please point out what is wrong.?

int(int(int((4*x),x,0,1),y,0,1),z,0,1)
error: Undefined function 'int' for input arguments of type 'double'

Thank You very much

Anupam

Answer 1

syms x y z

int(int(int((4*x),x,0,1),y,0,1),z,0,1)