Splitting up curves The unit circle x2 + y2 = 1 consists of four one-to-one functions, f1(...

Splitting up curves The unit circle x2 + y2 = 1 consists of four one-to-one functions, f1(x), f2(x), f3(x), and f4(x) (see figure).

a. Find the domain and a formula for each function.

b. Find the inverse of each function and write it as y = f−1(x).