what is wrong with matlab?

this is the block I made in matlab simulink, with function:

 if true
function trans_signal = fcn(a,w,t)
trans_signal = a*cosd(w*t);
  end

and display gives an answer in the negative -1.034 whereas it should be 0.8426. I tried the same in command window:

if true
  >> a=1.1;
>> w=40000;
>> t=10;
>> a*cosd(w*t)
ans =
  0.8426
end
Where am I wrong? It gives correct ans in command window and wrong answer in simulink.

[Ameer Hamza]

Are you sure that your simulation is running for 10 seconds? I just tried it and it is giving the correct value. Which MATLAB version are you using?