To me, in my spiritual life, this is somewhat of a warning. Those mathematical terms might be a stretch for all the thoughts that multiply in my head but God is showing me that anxious thoughts multiplied indicate I need more of Him or I will get a quantity obtained by multiplication, which I don't want. (Psalm 94:19)
As Chuck Swindoll states in the "anxiety" chapter 3, Christ at the Crossroads, (my) problems, "multiply" when I insert "my" solutions, try to work them out by "myself "or allow "my" own "fear" of inadequacy to creep in. The product from the multiplication of those problems is an answer I don't like. I become "afraid."
Clearly the answer for the multiplying of anxious thoughts is fear. "Fear with inadequacy."
Multiplying anxious thoughts becomes a deep-seeded fear much too heavy for me to carry around----so I choose thought multiplicands of love & truth, given by God. For He has not given us "fear but power, love and a sound mind." (2 Timothy 1:7) I'll take those "products" any day.