Why doesn't matlab plot both my graphs?

I want to plot 4 functions on the same graph (I only know VERY BASIC matlab - please, no negative comments, I'm enrolled in a course for this, and this is the weeks practice q's). but every time I plot more than 1 graph it throws an error and doesn't plot it. I cannot understand why, as in previous questions I have done exactly the same thing.

This is my code below:

>> d0 = @(t) 10.*cos(t.*(2.*pi))

d0 =

    function_handle with value:

      @(t)10.*cos(t.*(2.*pi))

>> fplot(d0, [0,5], 'k')
>> fplot(d0, [0,5], 'k')
>> hold on

The above part works fine, but then I try to do the second graph:

>> d1 = @(t) (10.*cos(t.*(2.*pi)))/exp(t.*0.2)

d1 =

    function_handle with value:

      @(t)(10.*cos(t.*(2.*pi)))/exp(t.*0.2)

>> fplot(d1, [0,5], '--r')
Warning: Function behaves unexpectedly on array inputs. To improve performance,
properly vectorize your function to return an output with the same size and shape as
the input arguments. 
> In matlab.graphics.function.FunctionLine>getFunction
  In matlab.graphics.function.FunctionLine/updateFunction
  In matlab.graphics.function.FunctionLine/set.Function_I
  In matlab.graphics.function.FunctionLine/set.Function
  In matlab.graphics.function.FunctionLine
  In fplot>singleFplot (line 226)
  In fplot>@(f)singleFplot(cax,{f},limits,extraOpts,args) (line 185)
  In fplot>vectorizeFplot (line 185)
  In fplot (line 156)

When I graph d1 first, it works. But then when I try to do d0 it doesn't do anything.

Thank you for any help and guidance.

Answer 1

[Walter Roberson]

d1 = @(t) (10.*cos(t.*(2.*pi)))./exp(t.*0.2)

[Tanya Van Wyk]

Thank you! Had no idea one had to place a period before the division as well - I've been stuck on this for 3hrs...so simple