Anki Deck Changes

Commit: 3ba641a7 - hasta la vista

Author: lhorva <lhorva@student.ethz.ch>

Date: 2026-01-21T13:22:35+01:00

Changes: 10 note(s) changed (0 added, 10 modified, 0 deleted)

ℹ️ Cosmetic Changes Hidden: 6 note(s) had formatting-only changes and are not shown below • 5 mixed cosmetic changes

Note 1: ETH::DiskMat

Deck: ETH::DiskMat
Note Type: Horvath Classic
GUID: L[2O7285Lj
modified

Before

Front

ETH::1._Semester::DiskMat::6._Logic::6._Predicate_Logic_(First-order_Logic)::8._Derivation_Rules
Universal Instantiation:

Back

ETH::1._Semester::DiskMat::6._Logic::6._Predicate_Logic_(First-order_Logic)::8._Derivation_Rules
Universal Instantiation:

For any formula \(F\) and any term \(t\) we have \[\forall x F \models F[x/t]\]

After

Front

ETH::1._Semester::DiskMat::6._Logic::6._Predicate_Logic_(First-order_Logic)::8._Derivation_Rules
What is the definition of universal instantiation?

Back

ETH::1._Semester::DiskMat::6._Logic::6._Predicate_Logic_(First-order_Logic)::8._Derivation_Rules
What is the definition of universal instantiation?

For any formula \(F\) and any term \(t\) we have: \[\forall x F \models F[x/t]\]
Field-by-field Comparison
Field Before After
Front <b>Universal</b> <b>Instantiation</b>: <b>What is the definition of universal instantiation?</b>
Back For any formula&nbsp;\(F\)&nbsp;and any term&nbsp;\(t\)&nbsp;we have&nbsp;\[\forall x F \models F[x/t]\] For any formula&nbsp;\(F\)&nbsp;and any term&nbsp;\(t\)&nbsp;we have:&nbsp;\[\forall x F \models F[x/t]\]
Tags: ETH::1._Semester::DiskMat::6._Logic::6._Predicate_Logic_(First-order_Logic)::8._Derivation_Rules

Note 2: ETH::DiskMat

Deck: ETH::DiskMat
Note Type: Horvath Cloze
GUID: Oj3Xy8Rn2M
modified

Before

Front

ETH::1._Semester::DiskMat::6._Logic::6._Predicate_Logic_(First-order_Logic)::7._Normal_Forms
Skolem Normal Form has only universal quantifiers.
It is equisatisfiable (not equivalent!) to the original formula.

Back

ETH::1._Semester::DiskMat::6._Logic::6._Predicate_Logic_(First-order_Logic)::7._Normal_Forms
Skolem Normal Form has only universal quantifiers.
It is equisatisfiable (not equivalent!) to the original formula.

After

Front

ETH::1._Semester::DiskMat::6._Logic::6._Predicate_Logic_(First-order_Logic)::7._Normal_Forms
Skolem normal form has no existance quantifiers.
It is equisatisfiable (not equivalent!) to the original formula.

Back

ETH::1._Semester::DiskMat::6._Logic::6._Predicate_Logic_(First-order_Logic)::7._Normal_Forms
Skolem normal form has no existance quantifiers.
It is equisatisfiable (not equivalent!) to the original formula.
Field-by-field Comparison
Field Before After
Text Skolem Normal Form has {{c1::only universal quantifiers}}.<br>It is {{c2::<i>equisatisfiable</i> (not equivalent!)}} to the original formula. Skolem normal form has {{c1::no existance quantifiers}}.<br>It is {{c2::<i>equisatisfiable</i> (not equivalent!)}} to the original formula.
Tags: ETH::1._Semester::DiskMat::6._Logic::6._Predicate_Logic_(First-order_Logic)::7._Normal_Forms

Note 3: ETH::DiskMat

Deck: ETH::DiskMat
Note Type: Horvath Classic
GUID: kH8u]Z~QoA
modified

Before

Front

ETH::1._Semester::DiskMat::6._Logic::6._Predicate_Logic_(First-order_Logic)::7._Normal_Forms
Prenex form defintion:

Back

ETH::1._Semester::DiskMat::6._Logic::6._Predicate_Logic_(First-order_Logic)::7._Normal_Forms
Prenex form defintion:

A formula of the form \[Q_1 x_1 \ Q_2 x_2 \ \dots \ Q_n x_n G\]where the \(Q_i\) are arbitrary quantifiers and \(G\) is a formula free of quantifiers.

After

Front

ETH::1._Semester::DiskMat::6._Logic::6._Predicate_Logic_(First-order_Logic)::7._Normal_Forms
What is the definition of the prenex form?

Back

ETH::1._Semester::DiskMat::6._Logic::6._Predicate_Logic_(First-order_Logic)::7._Normal_Forms
What is the definition of the prenex form?

A formula of the form \[Q_1 x_1 \ Q_2 x_2 \ \dots \ Q_n x_n G\]where the \(Q_i\) are arbitrary quantifiers and \(G\) is a formula free of quantifiers.
Field-by-field Comparison
Field Before After
Front <b>Prenex</b>&nbsp;form defintion: <b>What is the definition of the prenex form?</b>
Tags: ETH::1._Semester::DiskMat::6._Logic::6._Predicate_Logic_(First-order_Logic)::7._Normal_Forms

Note 4: ETH::DiskMat

Deck: ETH::DiskMat
Note Type: Horvath Classic
GUID: wJ,ON3lFCv
modified

Before

Front

ETH::1._Semester::DiskMat::5._Algebra::8._Finite_Fields::2._Constructing_Extension_Fields

Give an example of an extension field constructed from polynomials.

Back

ETH::1._Semester::DiskMat::5._Algebra::8._Finite_Fields::2._Constructing_Extension_Fields

Give an example of an extension field constructed from polynomials.


\(\mathbb{R}[x]_{x^2+1}\) is a field, isomorphic to \(\mathbb{C}\) (the complex numbers).

Explanation: \(x^2 + 1\) is irreducible over \(\mathbb{R}\) (no real roots). Elements of \(\mathbb{R}[x]_{x^2+1}\) are of the form \(a + bx\) where \(x^2 = -1\), which corresponds exactly to complex numbers \(a + bi\).

There are no other extension fields on \(\mathbb{R}\) that aren't isomorphic to \(\mathbb{C}\).

After

Front

ETH::1._Semester::DiskMat::5._Algebra::8._Finite_Fields::2._Constructing_Extension_Fields

Give an example of an extension field constructed from polynomials.

Back

ETH::1._Semester::DiskMat::5._Algebra::8._Finite_Fields::2._Constructing_Extension_Fields

Give an example of an extension field constructed from polynomials.


\(\mathbb{R}[x]_{x^2+1}\) is a field, isomorphic to \(\mathbb{C}\) (the complex numbers).

Explanation: \(x^2 + 1\) is irreducible over \(\mathbb{R}\) (no real roots). Elements of \(\mathbb{R}[x]_{x^2+1}\) are of the form \(a + bx\) where \(x^2 = -1\), which corresponds exactly to complex numbers \(a + bi\).

Every proper finite extension field of \(\mathbb{R}\) is isomorphic to \(\mathbb{C}\).

Field-by-field Comparison
Field Before After
Back <p>\(\mathbb{R}[x]_{x^2+1}\) is a field, <strong>isomorphic to \(\mathbb{C}\)</strong> (the complex numbers).</p> <p><strong>Explanation</strong>: \(x^2 + 1\) is irreducible over \(\mathbb{R}\) (no real roots). Elements of \(\mathbb{R}[x]_{x^2+1}\) are of the form \(a + bx\) where \(x^2 = -1\), which corresponds exactly to complex numbers \(a + bi\).</p> <p>There are no other extension fields on \(\mathbb{R}\) that aren't isomorphic to \(\mathbb{C}\).</p> <p>\(\mathbb{R}[x]_{x^2+1}\) is a field, <strong>isomorphic to \(\mathbb{C}\)</strong> (the complex numbers).</p> <p><strong>Explanation</strong>: \(x^2 + 1\) is irreducible over \(\mathbb{R}\) (no real roots). Elements of \(\mathbb{R}[x]_{x^2+1}\) are of the form \(a + bx\) where \(x^2 = -1\), which corresponds exactly to complex numbers \(a + bi\).</p> <p>Every proper finite extension field of&nbsp;\(\mathbb{R}\) is isomorphic to \(\mathbb{C}\).</p>
Tags: ETH::1._Semester::DiskMat::5._Algebra::8._Finite_Fields::2._Constructing_Extension_Fields
↑ Top