Why isn't Expand[] grouping terms by order?

*To*: mathgroup at smc.vnet.net*Subject*: [mg87825] Why isn't Expand[] grouping terms by order?*From*: <p at dirac.org>*Date*: Fri, 18 Apr 2008 02:38:56 -0400 (EDT)

Consider this: In[19]:= Expand[ (1+a*x)*(1+b*x), x] 2 Out[19]= 1 + a x + b x + a b x How can I coax Mathematica to give me this, instead: 2 Want[19]= 1 + (a + b) x + a b x Why isn't Mathematica reporting the answer in terms of powers of x? Thanks!