Is there a way to do the following?

lets say there is a range spanning rows 1,2,3, with 3 columns
A1 = B1 + C1
A2 = B2 + C2
A3 = B3 + C3


Lets say I enter a blank row at 2
A1 = B1 + C1

A3 = B3 + C3
A4 = B4 + C4

Is there a way to automatically fill in the formuals on row 2 so when
I insert a blank row I get this:
A1 = B1 + C1
A2 = B2 + C2 <the newly filled in formula
A3 = B3 + C3
A4 = B4 + C4



The idea behind this is I'd prefer not to have to prefil lots of cells
with formulas, and instead expand them as needed