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Section 8.2 Logic Networks
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S e c t i o n 8 . 2 review
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• Find the truth function corresponding to a given
Boolean expression or logic network.
• Construct a logic network with the same truth function as a given Boolean expression.
• Write a Boolean expression with the same truth
function as a given logic network.
• Write the Boolean expression in canonical sum-ofproducts form for a given truth function.
• Find a network composed only of NAND gates that
has the same truth function as a given network with
AND gates, OR gates, and inverters.
• Find a truth function that satisfies the description of
a particular problem.
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• We can effectively convert information from any of
the following three forms to any other form:
truth function 4 Boolean expression 4
logic network
• A Boolean expression can sometimes be converted
to a simpler, equivalent expression using the properties of Boolean algebra, thus producing a simpler
network for a given truth function.
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exeRciSeS 8.2
For Exercises 1–4, write a truth function and construct a logic network using AND gates, OR gates, and inverters
for each of the given Boolean expressions.
1. (x 1
′ + x 2 )x 3
2. (x 1 + x 2
′) + x 1
′x 3
3. x 1
′x 2 + (x 1 x 2 )′
4. (x 1 + x 2 )′x 3 + x 3
′
For Exercises 5–8, write a Boolean expression and a truth function for each of the logic networks shown.
5.
6.
7.