申論題

Problem 2: (20 points) Consider the expression

(a) (10%) Prove by induction that it represents an odd-parity function, that is, it evaluates to 1 if and only if the assignment to variables X₁,...,X_n contains an odd number of 1's. (For example, the assignment (X₁, X₂, X₃, X₄)= (1,0,0,0) contains one 1.)