PRECALCULUS:GRAPHICAL,...-NASTA ED.
PRECALCULUS:GRAPHICAL,...-NASTA ED.
10th Edition
ISBN: 9780134672090
Author: Demana
Publisher: PEARSON
Expert Solution & Answer
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Chapter B.2, Problem 10E
Solution

(a.)

To Show: The given expression is a tautology, using truth table.

It has been determined that the given expression is a tautology.

Given:

  pqprq

Concept used:

If the truth value of an expression in its truth table is always true, then it is a tautology.

Calculation:

The given expression is pqprq .

The truth table for the given expression is as follows:

    pqrpqprprqpqprq
    FFFTFTT
    FFTTFTT
    FTFTFTT
    FTTTFTT
    TFFFFTT
    TFTFTFT
    TTFTFTT
    TTTTTTT

It can be seen that the truth value for the given expression is always true.

Hence, the given expression is a tautology.

Conclusion:

It has been determined that the given expression is a tautology.

(b.)

To Show: The given expression is a tautology, using truth table.

It has been determined that the given expression is a tautology.

Given:

  pqpq

Concept used:

If the truth value of an expression in its truth table is always true, then it is a tautology.

Calculation:

The given expression is pqpq .

The truth table for the given expression is as follows:

    pqpqpqppqpq
    FFTFT
    FTTFT
    TFFFT
    TTTTT

It can be seen that the truth value for the given expression is always true.

Hence, the given expression is a tautology.

Conclusion:

It has been determined that the given expression is a tautology.

(c.)

To Show: The given expression is a tautology, using truth table.

It has been determined that the given expression is a tautology.

Given:

  pqqq

Concept used:

If the truth value of an expression in its truth table is always true, then it is a tautology.

Calculation:

The given expression is pqqq .

The truth table for the given expression is as follows:

    pqqpqpqqpqqq
    FFTTTT
    FTFTFT
    TFTFFT
    TTFTFT

It can be seen that the truth value for the given expression is always true.

Hence, the given expression is a tautology.

Conclusion:

It has been determined that the given expression is a tautology.

(d.)

To Show: The given expression is a tautology, using truth table.

It has been determined that the given expression is a tautology.

Given:

  pqqrpr

Concept used:

If the truth value of an expression in its truth table is always true, then it is a tautology.

Calculation:

The given expression is pqqrpr .

The truth table for the given expression is as follows:

    pqrpqqrpqqrprpqqrpr
    FFFTTTTT
    FFTTTTTT
    FTFTFFTT
    FTTTTTTT
    TFFFTFFT
    TFTFTFTT
    TTFTFFFT
    TTTTTTTT

It can be seen that the truth value for the given expression is always true.

Hence, the given expression is a tautology.

Conclusion:

It has been determined that the given expression is a tautology.