* lib/matrix.rb: Fix typo in rdoc

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@40382 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

lib/matrix.rb

@@ -1759,7 +1759,7 @@ class Vector
   end
 
   #
-  # Returns the cross product of this vector whit the other.
+  # Returns the cross product of this vector with the other.
   #   Vector[1, 0, 0].cross_product Vector[0, 1, 0]   => Vector[0, 0, 1]
   #
   def cross_product(v)