Let M(x, y) be "x has sent y an e-mail message" and T(x, y) be "...

Let M(x, y) be "x has sent y an e-mail message" and T(x, y) be " x has telephoned y, " where the domain consists of all students in your class. Use quantifiers to express each of these statements.

g. There is a student in your class who sent every one else in your class an email message.

I answer ∃x( x ≠ y ∧ ∀? M (x, y) )

But answer on text book is ∃x( x ≠ y → ∀? M (x, y) )

i. There are two different students in your class who fave sent each other e-mail messages.

I answer ∃x∃y( x ≠ y→ ∀? (M (x, y) ∧ M( y, x)))

But answer on text book is ∃x∃y( x ≠ y ∧ ∀? (M (x, y) ∧ M( y, x)))

I am confused about the use of → and ∧ on almost all the question.

Can someone explain two differences here, and perhaps explain it by translating to English?

Expert Solution

Colby Messinger answered 2 years ago

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