A function F(A,B,C) defined by three Boolean variables A, B and C when expressed as sum of products is given by
F=¯¯¯¯A.¯¯¯¯B.¯¯¯¯C+¯¯¯¯A.B.¯¯¯¯C+A.¯¯¯¯B.¯¯¯¯C
where, ¯¯¯¯A,¯¯¯¯B, and ¯¯¯¯C are the complements of the respective variables. The product of sums (POS) form of the function F is