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De Morgan’s laws presentation. De Morgan’s laws. De Morgan’s laws allow us to simplify Boolean expressions that use AND or OR. They can be summarised as:. Invert the inputs. Combine them using the ‘other’ operation. Invert the result. Law 1. De Morgan’s laws. — —— —.
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De Morgan’s laws De Morgan’s laws allow us to simplify Boolean expressions that use AND or OR. They can be summarised as: • Invert the inputs • Combine them using the ‘other’ operation • Invert the result
Law 1 De Morgan’s laws ———— A + B = A . B
Law 1 De Morgan’s laws ———— A + B = A . B Law 2 ———— A . B = A + B
De Morgan’s laws To see why the first law is true, draw up a truth table:
De Morgan’s laws Invert input A: __
De Morgan’s laws Invert input B: __ __
De Morgan’s laws ‘AND’ the two inverted inputs …. __ __ __ __
De Morgan’s laws …. and finally, invert again : __ __ ——— __ __
De Morgan’s laws So the truth tables for both sides of law 1 are identical ———
De Morgan’s laws The second law can be verified in the same way:
De Morgan’s laws Invert input A: __
De Morgan’s laws Invert input B: __ __
De Morgan’s laws ‘OR’ the two inverted inputs …. __ __ __ __
De Morgan’s laws …. and finally, invert again : __ __ ——— __ __
De Morgan’s laws So the truth tables for both sides of law 2 are identical ———
