3.3 The characteristic function of the set o function from universal set to 10, 1) .o Definition 3. 6: let u be the universal set and let acu. the characteristic function of a is defined as a function from U to 10, 1 by the following yA(x) 0 x a3.3 The Characteristic function of the set ❖ function from universal set to {0,1} ❖ Definition 3.6: Let U be the universal set, and let AU. The characteristic function of A is defined as a function from U to {0,1} by the following:      = x A x A x A 0 1  ( )