a. XYZ

20. When more than two vincula of equal length extend over the same

b. AB+X

c. (R+S) T

time by using the DOUBLE NEGATIVE law. For example, A = A; CD

d. LMT

= CD; X+Y = X+Y; etc.

By using the DOUBLE NEGATIVE law, ____________

vincula may be removed at the same time.

two

21.

Simplify the following Boolean expressions, using the DOUBLE

NEGATIVE law.

a. AB + C

b. B + F + GH

c. (R + S) T + Z

d. AB + BD

a. AB+C

22. Simplify the following expressions, using the laws that have been

b. B+F+GH

covered.

c. (R+S) T+Z

a. C + DG + FD + G + C

d. AB+BD

b. (Q +R + S) +S + (R + Q)

c. (MNP + Q) L + K

d. (WXY + Z) (Z + WXY)