Matlab Symbolic function operation and CONJ

Clc
Clear
Syms X1 X2 X3 x4 X5 X6
x=[x1; x2; x3; x4; x5; X6];
Dxx=kron (x. ', X. '); % Note that when using symbolic function operations, you need to add a point after the variable "."

% otherwise the default is the complex number, the result contains Conj
The result of the operation of the% Dxx=kron (x ', X ') is:
% DXX =
%
% [Conj (x1) ^2, Conj (x1) *conj (x2), Conj (x1) *conj (x3), CONJ (x1) *conj (x4), Conj (x1) *conj (X5), Conj (x1) *conj (x6),...
% Conj (x1) *conj (x2), Conj (x2) ^2, Conj (x2) *conj (x3), Conj (x2) *conj (x4), Conj (x2) *conj (X5), Conj (x2) *conj (x6),...
% Conj (x1) *conj (x3), Conj (x2) *conj (x3), Conj (x3) ^2, Conj (x3) *conj (x4), Conj (x3) *conj (X5), Conj (x3) *conj (x6),...
% Conj (x1) *conj (x4), Conj (x2) *conj (x4), Conj (x3) *conj (x4), Conj (x4) ^2, Conj (x4) *conj (X5), Conj (x4) *conj (x6),...
% Conj (x1) *conj (X5), Conj (x2) *conj (X5), Conj (x3) *conj (X5), Conj (x4) *conj (X5), Conj (X5) ^2, Conj (X5) *conj (X6),...
% Conj (x1) *conj (X6), Conj (x2) *conj (X6), Conj (x3) *conj (X6), Conj (x4) *conj (X6), Conj (X5) *conj (X6), Conj (X6) ^2]
The result of the operation of% Dxx=kron (x. ', X. ') is
% DXX =
%
% [X1^2, x1*x2, x1*x3, x1*x4, x1*x5, x1*x6, x1*x2, x2^2, x2*x3, x2*x4, x2*x5, x2*x6,...
% x1*x3, x2*x3, x3^2, x3*x4, x3*x5, x3*x6, x1*x4, x2*x4, x3*x4, x4^2, x4*x5, x4*x6,...
% x1*x5, x2*x5, x3*x5, x4*x5, x5^2, x5*x6, x1*x6, x2*x6, x3*x6, x4*x6, x5*x6, x6^2]

The picture shows the results of the operation of Dxx=kron (x. ', X. ')

Complex