//chapter28
//example28.8
//page607

printf("i) Y = A + A` . B \n")
printf("   By theorem 16 \n")
printf("   Y = A + A . B + A` . B \n")
printf("     = A + B ( A + A`) \n")
printf("   By theorem 3 \n")
printf("   Y = A + B \n \n")

printf("ii) Y = A . B + A` . C + B . C \n")
printf("      = A . B + A` . C + B . C ( A + A` )\n")
printf("      = A . B + A` . C + A . B . C + A` . B . C \n")
printf("      = A . B ( 1 + C ) + A` . C( 1 + B ) \n")
printf("      = A . B + A` . C \n")