This seems like it should be easy but its got me beat:
$$c = {a \over {a + b} }$$
What is:
$$\partial c \over \partial a$$
?
This seems like it should be easy but its got me beat:
$$c = {a \over {a + b} }$$
What is:
$$\partial c \over \partial a$$
?
$a/(a+b)= 1- b/(a+b)$ Thus the derivative is $b(a+b)^-2$