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Exercise 1.6.3: Translating mathematical statements in English into logical expressions. info About Consider the following statements in English. Write a logical expression with the same meaning. The domain is the set of all real numbers. (a) There is a number whose cube is equal to 2. (b) The square of every number is at least 0. (c) There is a number that is equal to its square. (d) Every number is less than or equal to its square..

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Answer:

a) Эx ∈ R ⊇ x³ = 2

b) ∀x ∈ R, x² ≥ 0

c) Эx ∈ R ⊇ x³ = x

d) ∀x ∈ R, x ≤ x²

Explanation:

Given the data in the question;

let us first go through some symbols and their possible meanings;

Э ⇒ there exists

∀ ⇒ for all

∈ ⇒ belongs to or set membership or element of the set

⊇ ⇒ such that

now;

a) There is a number whose cube is equal to 2

let x represent the number; so

Эx ∈ R ⊇ x³ = 2

b) The square of every number is at least 0

x² ≥ 0, ∀x ∈ R

∀x ∈ R, x² ≥ 0

c) There is a number that is equal to its square

Эx ∈ R ⊇ x³ = x

d) Every number is less than or equal to its square.

x ≤ x², ∀x ∈ R

∀x ∈ R, x ≤ x²