Maxima integral not evaluating from screenshot

[PhizKid]

Here is a screenshot: http://i.imgur.com/AG3EL.png

Does anyone know what I am doing wrong here? I'm used to Mathematica because it's more syntax-lax but I guess in Maxima it's more explicit and strict. I've looked at examples online and they seem no different than what I have input, so I don't get what's wrong.

 

[NemoReally]

try 4*x instead of 4x ... I think you need the multiplication operator