Just quickly skimmed a bit of the book, but I have never seen or heard any of those tricks (German here) with the exception of the formula triangle (still have

Just quickly skimmed a bit of the book, but I have never seen or heard any of those tricks (German here) with the exception of the formula triangle (still have that in mind for Ohm's law). That being said, I mainly need it for remembering the relationship and have no trouble solving the formula for a different quantity.