This is the beginning of the derivation of equation of motion from the Solow model (Romer, 2019):
My question is: is this the total derivative (w.r.t. ultimate source of change "t")? If yes, why there is a minus sign in front of the 2nd and 3rd term? I assume because they are in the denominator. But I was not able find any rules for this on net. Everywhere are only "+" symbols. Thanks.
This is how I did it. Is it wrong? I did total derivative and got the same result as in the textbook: