MathDB
Putnam 1958 February A5

Source: Putnam 1958 February

July 18, 2022
Putnamcalculusintegrationequation

Problem Statement

Show that the integral equation f(x,y)=1+0x0yf(u,v)dudvf(x,y) = 1 + \int_{0}^{x} \int_{0}^{y} f(u,v) \, du \, dv has at most one solution continuous for 0x1,0y1.0\leq x \leq 1, 0\leq y \leq 1.