When there are no plus signs (these things "+") then you can't be
talking about a SUM!  So I assumed you meant a PRODUCT, and posted
this:






 If you REALLY meant a sum, then repost putting in some plus signs.
When there are no plus signs between things, everybody assumes 
they are to be multiplied, not added.
Edwin
If you REALLY meant a sum, then repost putting in some plus signs.
When there are no plus signs between things, everybody assumes 
they are to be multiplied, not added.
Edwin