Issues plotting an equation.

I'm having difficultly getting an equation to run for a homework problem I'm working on. I'm hoping someone can help me get the equation to be functional, please don't help me complete the problem beyond that point.

My current code is

clear variables

clc
t=0:.5:5;
w_d=4;
for o=1
x=((10*exp(-o*t))*(cos(w_d*t)))-((0.2*exp(-o*t))*(sin(w_d*t)));
    plot(x,t)
end

The error I'm receiving is

Error using  * 
Incorrect dimensions for matrix multiplication. Check
that the number of columns in the first matrix matches
the number of rows in the second matrix. To perform
elementwise multiplication, use '.*'.

Error in Untitled9 (line 6)
x=((10*exp(-o*t))*(cos(w_d*t)))-((0.2*exp(-o*t))*(sin(w_d*t)));

The homework problem is:

As mentioned previously, I only want help making the equation work. Thank you!

Answer 1

[VBBV]

%f true
clc
t=0:.5:5;
w_d=4;
o=1
x=(10*exp(-o*t).*(cos(w_d*t))-(0.2*exp(-o*t)).*(sin(w_d*t)));
  plot(x,t)

Try above with element wise operator