spelling mistake

the `function` in "You'd like to know the type of a function without using typeof. " must be `object`.

Author: island205

chapters/classes_and_objects/type-function.md

@@ -5,7 +5,7 @@ chapter: Classes and Objects
 ---
 ## Problem
 
-You'd like to know the type of a function without using typeof. (See http://javascript.crockford.com/remedial.html for more information on why typeof is pretty inferior.)
+You'd like to know the type of a object without using typeof. (See http://javascript.crockford.com/remedial.html for more information on why typeof is pretty inferior.)
 
 ## Solution