Question

what is C&D law in math?

Answer 1

mathematics. Distributive law, in mathematics, the law relating the operations of multiplication and addition, stated symbolically, a(b + c) = ab + ac; that is, the monomial factor a is distributed, or separately applied, to each term of the binomial factor b + c, resulting in the product ab + ac.

Answer 2

C & D means Componendo and Dividendo law.