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Grade 11 • Science Mathematics • Unit 1: Algebra

Chapter 1: Logic, Sets and Real Number System

Exercise 1.1 — Logic

Questions and answers below follow the supplied chapter text. Mathematical expressions use the site’s KaTeX renderer and all truth tables are real, horizontally scrollable HTML tables.

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Source verification notes

The supplied file contains Exercise 1.1 only. Its ending shows 19 numbered MCQ slots, but no MCQ question statements or options; only 17 answer/hint fragments are discernible, and their numbering cannot be verified. They are not treated as a verified answer key.

Several solution typos and truth-table mismatches are identified beside the affected answers. Where the intended expression is clear, tables are recalculated from the printed question. Ambiguous source wording is left flagged instead of guessed.

Question 1

(a)

Answer and working

(b)

Answer and working

(c)

Answer and working

(d)

Answer and working

(e)

Answer and working

(f)

Answer and working

Question 2

(a)

Answer and working

(b)

Answer and working

(c)

Answer and working

(d)

Answer and working

(e)

Answer and working

(f)

Answer and working

(g)

Answer and working

(h)

Answer and working

Question 3

(a)

Answer and working

(b)

Answer and working

(c)

Answer and working

Source note:

(d)

Answer and working

Question 4

(a)

Truth table for (¬p) ∧ q
TTFF
TFFF
FTTT
FFTF

Answer and working

(b)

Truth table for (¬p) ∨ (¬q)
TTFFF
TFFTT
FTTFT
FFTTT

Answer and working

(c)

Truth table for ¬(p ∧ q)
TTTF
TFFT
FTFT
FFFT

Answer and working

(d)

Truth table for ¬[p ∨ (¬q)]
TTFTF
TFTTF
FTFFT
FFTTF

Answer and working

(e)

Truth table for (p → q) ∧ (q → p)
TTTTT
TFFTF
FTTFF
FFTTT

Answer and working

(f)

Truth table for (¬p ∨ q) → (p ∨ q)
TTFTTT
TFFFTT
FTTTTT
FFTTFF

Answer and working

Source note:

(g)

Truth table for [p ∧ (p → q)] → q
TTTTT
TFFFT
FTTFT
FFTFT

Answer and working

(h)

Truth table for (p → q) ↔ (¬p ∨ q)
TTTFTT
TFFFFT
FTTTTT
FFTTTT

Answer and working

(i)

Truth table for (p ↔ q) ∨ (q ↔ r)
TTTTTT
TTFTFT
TFTFFF
TFFFTT
FTTFTT
FTFFFF
FFTTFT
FFFTTT

Answer and working

Question 5

(a)

Given values for p ∧ q
TFF

Answer and working

(b)

Given values for p ∨ (¬q)
TFTT

Answer and working

(c)

Given values for (¬p) ∧ (¬q)
TFFTF

Answer and working

(d)

Given values for q ∨ (p ∧ s)
TFFFF

Answer and working

(e)

Given value for ¬(¬p)
TFT

Answer and working

(f)

Given values for (p ∨ q) ∧ (r ∨ s)
TFTFTTT

Answer and working

Question 6

(a)

Truth table for p ∧ ¬p
TFFF
FTFF

Answer and working

(b)

Truth table for the commutative law of disjunction
TTTT
TFTT
FTTT
FFFF

Answer and working

(c)

Truth table for ¬[p ∨ (¬q)] ≡ (¬p) ∧ q
TTFTFFF
TFTTFFF
FTFFTTT
FFTTFTF

Answer and working

Source note:

(d)

Truth table for ¬[(¬p) ∧ q] ≡ p ∨ ¬q
TTFFTFT
TFFFTTT
FTTTFFF
FFTFTTT

Answer and working

Question 7

(a)

Answer and working

(b)

Answer and working

(c)

Answer and working

(d)

Answer and working

(e)

Answer and working

Question 8

(a)

Truth values for p ∨ q
TFT

Answer and working

(b)

Truth values for p ∧ q
FTF

Answer and working

(c)

Truth values for p → q
TTT

Answer and working

(d)

Truth values for (p ∨ q) → r
FTFTF

Answer and working

(e)

Truth values for (p → q) → r
FTTTT

Answer and working

Source note:

(f)

Truth table for p ↔ q
TTTTT

Answer and working

Question 9

(a)

Answer and working

(b)

Answer and working

Source note:

(c)

Answer and working

Question 10

(a)

Truth table for p ∨ (¬p ∧ q)
TTFFT
TFFFT
FTTTT
FFTFF

Answer and working

(b)

Truth table for (p ∧ q) → (p ∨ q)
TTTTT
TFFTT
FTFTT
FFFFT

Answer and working

(c)

Truth table for ¬(p ∨ q) ∧ q
TTTFF
TFTFF
FTTFF
FFFTF

Answer and working

Source note:

(d)

Truth table for (p ∧ q) ∧ ¬(p ∨ q)
TTTTFF
TFFTFF
FTFTFF
FFFFTF

Answer and working

(e)

Truth table for [¬q ∧ (p → q)] → ¬p
TTFTFFT
TFTFFFT
FTFTFTT
FFTTTTT

Answer and working

(f)

Truth table for [(p ∧ q) → p] → (q ∧ ¬q)
TTTTFFF
TFFTTFF
FTFTFFF
FFFTTFF

Answer and working

MCQ material at the end of the source

The source shows nineteen numbered MCQ slots but no question statements or options. It contains fewer discernible answer/hint fragments, and their mapping to the numbered slots is unclear. The fragments are preserved here as incomplete source material only.