Error using * on matlab basic command

have an error using the * command not sure how to fix the line of code. it is the last bolded line before the commented out section

clc;
clear ;close all
v=0:0.1:100; % mlp
y = 0.35;
Amplitude = 0.35;
Peroid = 12;
Weight = 155.42;
c = 40;
k = 13.75;
Wn = sqrt(k/Weight);
W = 2*pi/12;
r = Wn/W;
zeta = c/2*(sqrt(Weight*k));
zetasq = zeta^2;
X = y*sqrt((1-r*v*zetasq*r*v.^2)./(((1-r.*v.^2.).^2.)+4*zetasq*r*v.^2.));




%v=0:0.1:100; % mlp
% 
% % displacement amplitude
% 
% X= 0.45* sqrt( 1+13.050*v.^2 ./(  (1-12.745*v.^2 ).^2 +(13.05*v.^2)  ) );
% 
figure(1)
plot(v,X)
grid on;
xlabel('velocity (Mph)');
ylabel('amplitude of X (ft)');
title('Amplitude of X vs velocity');

Answer 1

[KSSV]

clc;
clear ;close all
v=0:0.1:100; % mlp
y = 0.35;
Amplitude = 0.35;
Peroid = 12;
Weight = 155.42;
c = 40;
k = 13.75;
Wn = sqrt(k/Weight);
W = 2*pi/12;
r = Wn/W;
zeta = c/2*(sqrt(Weight*k));
zetasq = zeta^2;
X = y*sqrt((1-r*v*zetasq*r.*v.^2)./(((1-r.*v.^2.).^2.)+4*zetasq*r.*v.^2.));




%v=0:0.1:100; % mlp
% 
% % displacement amplitude
% 
% X= 0.45* sqrt( 1+13.050*v.^2 ./(  (1-12.745*v.^2 ).^2 +(13.05*v.^2)  ) );
% 
figure(1)
plot(v,X)
grid on;
xlabel('velocity (Mph)');
ylabel('amplitude of X (ft)');
title('Amplitude of X vs velocity');