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Cool Complex Numbers and Quadratics Notes PDF: Easy A Level Fun

View

Cool Complex Numbers and Quadratics Notes PDF: Easy A Level Fun

A Level Further Maths Complex Numbers and Matrices: A Comprehensive Guide

This guide covers essential topics in A Level Further Maths complex numbers and matrices, including complex number operations, Argand diagrams, and matrix arithmetic. It provides detailed explanations, examples, and visual representations to help students master these advanced mathematical concepts.

30/06/2022

3736

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

View

Complex Numbers: Foundations and Operations

Complex numbers are an extension of the real number system, incorporating imaginary numbers. They are essential in A Level Further Maths complex numbers studies.

Definition: A complex number is expressed as z = x + iy, where x is the real part, y is the imaginary part, and i is the square root of -1.

The guide introduces the concept of complex conjugates and arithmetic operations with complex numbers:

  1. Addition and subtraction of complex numbers
  2. Multiplication of complex numbers
  3. Division of complex numbers using the complex conjugate method

Example: (2 + 5i)(1 - 3i) = 17 - i

Highlight: When multiplying complex numbers, remember that i² = -1, which simplifies calculations.

The document also covers the solution of quadratic equations with complex roots, providing a solid foundation for more advanced topics in Complex numbers A Level further Maths.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

View

Argand Diagrams and Complex Number Representation

Argand diagrams are a crucial tool for visualizing complex numbers in a two-dimensional plane, making them an important topic in A level Further Maths complex numbers questions.

Definition: An Argand diagram is a method of plotting complex numbers on a 2D plane, where the x-axis represents the real part and the y-axis represents the imaginary part.

The guide explains how to plot complex numbers and their conjugates on an Argand diagram, demonstrating the geometric relationship between these numbers.

Example: For z₁ = 2 + i and z₂ = 1 + 3i, the guide shows how to plot these points and their sum on an Argand diagram.

The concept of modulus and argument is introduced, providing a polar representation of complex numbers:

  • Modulus: |z| = √(x² + y²)
  • Argument: arg(z) = tan⁻¹(y/x)

Vocabulary: The modulus-argument form of a complex number is z = r(cos θ + i sin θ), where r is the modulus and θ is the argument.

This section provides a solid foundation for understanding more advanced topics like locus of complex numbers solutions and Argand diagram inequalities.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

View

Matrices: Introduction and Basic Operations

The final section of the guide introduces matrices, an essential topic that often complements complex numbers in A Level Further Maths.

Definition: A matrix is a rectangular array of numbers arranged in rows and columns.

The guide covers fundamental matrix operations:

  1. Matrix addition and subtraction
  2. Scalar multiplication
  3. Matrix multiplication
  4. Matrix transposition

Example: The guide demonstrates how to multiply a 2x2 matrix by a 2x1 matrix, explaining the process step-by-step.

Highlight: When multiplying matrices, the number of columns in the first matrix must equal the number of rows in the second matrix.

The document also touches on the relationship between matrices and systems of linear equations, providing a foundation for solving more complex problems in A level further maths quadratic equations.

This comprehensive guide serves as an excellent resource for students preparing for A Level maths complex numbers and matrix-related questions, offering clear explanations and practical examples to reinforce understanding.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

View

Complex Numbers: Foundations and Operations

This page introduces the concept of complex numbers, a fundamental topic in A Level Further Maths complex numbers. It begins by placing complex numbers in the context of the number system hierarchy, from natural numbers to complex numbers.

Definition: A complex number is expressed as z = x + iy, where x is the real part, y is the imaginary part, and i is the square root of -1.

The page covers the solutions to quadratic equations, introducing imaginary solutions when the discriminant is negative. It provides examples of quadratic equations with real and complex solutions, demonstrating how to identify and solve them.

Example: For the equation x² - 2x + 10 = 0, the solutions are x = 1 ± 3i.

The guide emphasizes the importance of understanding complex numbers as pairs of real numbers, laying the groundwork for more advanced topics in Complex numbers A Level further Maths.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

View

Complex Conjugates and Arithmetic Operations

This section delves deeper into complex number operations, a crucial aspect of As further maths complex numbers notes.

Definition: The complex conjugate of z = x + iy, written as z* or z̄, is the complex number with the same real part and opposite imaginary part: z* = x - iy.

The page covers arithmetic operations with complex numbers:

  1. Addition and subtraction of complex numbers
  2. Multiplication of complex numbers
  3. Key facts about powers of i (i², i³, i⁴, etc.)

Example: (1 + i)⁴ = 1 + 4i + 6i² + 4i³ + i⁴ = -4 + 4i

The guide provides step-by-step explanations for these operations, helping students build confidence in manipulating complex numbers. This knowledge is essential for solving more advanced problems in A level Further Maths complex numbers questions.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

View

Division of Complex Numbers and Equating Real and Imaginary Parts

This page focuses on the division of complex numbers and the technique of equating real and imaginary parts, both important skills in A Level maths complex numbers.

Highlight: When dividing complex numbers, multiply both numerator and denominator by the complex conjugate of the denominator.

The guide provides a detailed example of complex number division:

(17 - i) ÷ (1 - 3i) = (17 + 51i + 3) ÷ (1 + 9) = (20 + 50i) ÷ 10 = 2 + 5i

The page also covers the technique of equating real and imaginary parts to solve equations involving complex numbers. This method is crucial for solving more complex problems in A level further maths quadratic equations.

Example: For the equation iz + 2i = 1 - 4i, the guide demonstrates how to solve for z by equating real and imaginary parts.

These skills form the foundation for more advanced topics in complex analysis and are essential for success in Complex numbers A Level further Maths.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

View

Argand Diagrams and Complex Number Representation

This page introduces Argand diagrams, a vital tool for visualizing complex numbers in As further maths complex numbers notes.

Definition: An Argand diagram is a method of plotting complex numbers on a 2D plane, where the x-axis represents the real part and the y-axis represents the imaginary part.

The guide demonstrates how to plot complex numbers and their conjugates on an Argand diagram, providing a geometric interpretation of complex number operations.

Example: The guide shows how to plot z₁ = 2 + i, z₂ = 1 + 3i, and their sum on an Argand diagram.

The page also introduces the concepts of modulus and argument:

  • Modulus: The magnitude of a complex number, represented by |z|
  • Argument: The angle between the positive real axis and the vector representing the complex number, denoted as arg(z)

These concepts are crucial for understanding more advanced topics like locus of complex numbers solutions and Argand diagram inequalities.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

View

Modulus-Argument Form and Polar Representation

This page delves deeper into the polar representation of complex numbers, an important topic in Complex numbers A Level further Maths.

Definition: The modulus-argument form of a complex number is z = r(cos θ + i sin θ), where r is the modulus and θ is the argument.

The guide provides formulas for converting between Cartesian (x + iy) and polar (r(cos θ + i sin θ)) forms:

  • r = √(x² + y²)
  • tan θ = y/x
  • x = r cos θ
  • y = r sin θ

Example: The guide demonstrates how to express √3 + i in modulus-argument form.

This representation is particularly useful for certain complex number operations and for solving problems involving Argand diagrams Further Maths Exam Questions.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

View

Introduction to Matrices

This page introduces matrices, a topic that often complements complex numbers in A Level Further Maths.

Definition: A matrix is a rectangular array of numbers arranged in rows and columns.

The guide covers basic matrix operations:

  1. Matrix addition and subtraction
  2. Scalar multiplication of matrices
  3. Matrix multiplication

Highlight: When multiplying matrices, the number of columns in the first matrix must equal the number of rows in the second matrix.

The page demonstrates how matrices can be used to represent systems of linear equations, providing a link between matrices and other areas of mathematics.

Example: The guide shows how to represent the system of equations s = 3u + 2v and t = 5u + 7v as a matrix equation.

This introduction to matrices lays the groundwork for more advanced topics in linear algebra and is essential for solving complex problems in A level further maths quadratic equations.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

View

Advanced Matrix Operations

This final page covers more advanced matrix operations, building on the foundations laid in the previous section.

The guide introduces the concept of matrix transposition:

Definition: The transpose of a matrix is obtained by interchanging its rows and columns.

The page provides examples of transposing matrices and explains the significance of the leading diagonal in this operation.

The guide also covers multiplication of matrices with different dimensions, demonstrating the process step-by-step:

Example: The multiplication of a 2x3 matrix by a 3x2 matrix is shown in detail.

These advanced matrix operations are crucial for solving complex problems in linear algebra and are often applied in various areas of A Level Further Maths.

This comprehensive guide serves as an excellent resource for students preparing for exams and seeking to master complex numbers and matrices in A Level maths complex numbers.

Can't find what you're looking for? Explore other subjects.

Knowunity is the #1 education app in five European countries

Knowunity has been named a featured story on Apple and has regularly topped the app store charts in the education category in Germany, Italy, Poland, Switzerland, and the United Kingdom. Join Knowunity today and help millions of students around the world.

Ranked #1 Education App

Download in

Google Play

Download in

App Store

Knowunity is the #1 education app in five European countries

4.9+

Average app rating

13 M

Pupils love Knowunity

#1

In education app charts in 12 countries

950 K+

Students have uploaded notes

Still not convinced? See what other students are saying...

iOS User

I love this app so much, I also use it daily. I recommend Knowunity to everyone!!! I went from a D to an A with it :D

Philip, iOS User

The app is very simple and well designed. So far I have always found everything I was looking for :D

Lena, iOS user

I love this app ❤️ I actually use it every time I study.

Cool Complex Numbers and Quadratics Notes PDF: Easy A Level Fun

A Level Further Maths Complex Numbers and Matrices: A Comprehensive Guide

This guide covers essential topics in A Level Further Maths complex numbers and matrices, including complex number operations, Argand diagrams, and matrix arithmetic. It provides detailed explanations, examples, and visual representations to help students master these advanced mathematical concepts.

30/06/2022

3736

 

12/12

 

Further Maths

113

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

Sign up to see the content. It's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Complex Numbers: Foundations and Operations

Complex numbers are an extension of the real number system, incorporating imaginary numbers. They are essential in A Level Further Maths complex numbers studies.

Definition: A complex number is expressed as z = x + iy, where x is the real part, y is the imaginary part, and i is the square root of -1.

The guide introduces the concept of complex conjugates and arithmetic operations with complex numbers:

  1. Addition and subtraction of complex numbers
  2. Multiplication of complex numbers
  3. Division of complex numbers using the complex conjugate method

Example: (2 + 5i)(1 - 3i) = 17 - i

Highlight: When multiplying complex numbers, remember that i² = -1, which simplifies calculations.

The document also covers the solution of quadratic equations with complex roots, providing a solid foundation for more advanced topics in Complex numbers A Level further Maths.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

Sign up to see the content. It's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Argand Diagrams and Complex Number Representation

Argand diagrams are a crucial tool for visualizing complex numbers in a two-dimensional plane, making them an important topic in A level Further Maths complex numbers questions.

Definition: An Argand diagram is a method of plotting complex numbers on a 2D plane, where the x-axis represents the real part and the y-axis represents the imaginary part.

The guide explains how to plot complex numbers and their conjugates on an Argand diagram, demonstrating the geometric relationship between these numbers.

Example: For z₁ = 2 + i and z₂ = 1 + 3i, the guide shows how to plot these points and their sum on an Argand diagram.

The concept of modulus and argument is introduced, providing a polar representation of complex numbers:

  • Modulus: |z| = √(x² + y²)
  • Argument: arg(z) = tan⁻¹(y/x)

Vocabulary: The modulus-argument form of a complex number is z = r(cos θ + i sin θ), where r is the modulus and θ is the argument.

This section provides a solid foundation for understanding more advanced topics like locus of complex numbers solutions and Argand diagram inequalities.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

Sign up to see the content. It's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Matrices: Introduction and Basic Operations

The final section of the guide introduces matrices, an essential topic that often complements complex numbers in A Level Further Maths.

Definition: A matrix is a rectangular array of numbers arranged in rows and columns.

The guide covers fundamental matrix operations:

  1. Matrix addition and subtraction
  2. Scalar multiplication
  3. Matrix multiplication
  4. Matrix transposition

Example: The guide demonstrates how to multiply a 2x2 matrix by a 2x1 matrix, explaining the process step-by-step.

Highlight: When multiplying matrices, the number of columns in the first matrix must equal the number of rows in the second matrix.

The document also touches on the relationship between matrices and systems of linear equations, providing a foundation for solving more complex problems in A level further maths quadratic equations.

This comprehensive guide serves as an excellent resource for students preparing for A Level maths complex numbers and matrix-related questions, offering clear explanations and practical examples to reinforce understanding.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

Sign up to see the content. It's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Complex Numbers: Foundations and Operations

This page introduces the concept of complex numbers, a fundamental topic in A Level Further Maths complex numbers. It begins by placing complex numbers in the context of the number system hierarchy, from natural numbers to complex numbers.

Definition: A complex number is expressed as z = x + iy, where x is the real part, y is the imaginary part, and i is the square root of -1.

The page covers the solutions to quadratic equations, introducing imaginary solutions when the discriminant is negative. It provides examples of quadratic equations with real and complex solutions, demonstrating how to identify and solve them.

Example: For the equation x² - 2x + 10 = 0, the solutions are x = 1 ± 3i.

The guide emphasizes the importance of understanding complex numbers as pairs of real numbers, laying the groundwork for more advanced topics in Complex numbers A Level further Maths.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

Sign up to see the content. It's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Complex Conjugates and Arithmetic Operations

This section delves deeper into complex number operations, a crucial aspect of As further maths complex numbers notes.

Definition: The complex conjugate of z = x + iy, written as z* or z̄, is the complex number with the same real part and opposite imaginary part: z* = x - iy.

The page covers arithmetic operations with complex numbers:

  1. Addition and subtraction of complex numbers
  2. Multiplication of complex numbers
  3. Key facts about powers of i (i², i³, i⁴, etc.)

Example: (1 + i)⁴ = 1 + 4i + 6i² + 4i³ + i⁴ = -4 + 4i

The guide provides step-by-step explanations for these operations, helping students build confidence in manipulating complex numbers. This knowledge is essential for solving more advanced problems in A level Further Maths complex numbers questions.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

Sign up to see the content. It's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Division of Complex Numbers and Equating Real and Imaginary Parts

This page focuses on the division of complex numbers and the technique of equating real and imaginary parts, both important skills in A Level maths complex numbers.

Highlight: When dividing complex numbers, multiply both numerator and denominator by the complex conjugate of the denominator.

The guide provides a detailed example of complex number division:

(17 - i) ÷ (1 - 3i) = (17 + 51i + 3) ÷ (1 + 9) = (20 + 50i) ÷ 10 = 2 + 5i

The page also covers the technique of equating real and imaginary parts to solve equations involving complex numbers. This method is crucial for solving more complex problems in A level further maths quadratic equations.

Example: For the equation iz + 2i = 1 - 4i, the guide demonstrates how to solve for z by equating real and imaginary parts.

These skills form the foundation for more advanced topics in complex analysis and are essential for success in Complex numbers A Level further Maths.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

Sign up to see the content. It's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Argand Diagrams and Complex Number Representation

This page introduces Argand diagrams, a vital tool for visualizing complex numbers in As further maths complex numbers notes.

Definition: An Argand diagram is a method of plotting complex numbers on a 2D plane, where the x-axis represents the real part and the y-axis represents the imaginary part.

The guide demonstrates how to plot complex numbers and their conjugates on an Argand diagram, providing a geometric interpretation of complex number operations.

Example: The guide shows how to plot z₁ = 2 + i, z₂ = 1 + 3i, and their sum on an Argand diagram.

The page also introduces the concepts of modulus and argument:

  • Modulus: The magnitude of a complex number, represented by |z|
  • Argument: The angle between the positive real axis and the vector representing the complex number, denoted as arg(z)

These concepts are crucial for understanding more advanced topics like locus of complex numbers solutions and Argand diagram inequalities.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

Sign up to see the content. It's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Modulus-Argument Form and Polar Representation

This page delves deeper into the polar representation of complex numbers, an important topic in Complex numbers A Level further Maths.

Definition: The modulus-argument form of a complex number is z = r(cos θ + i sin θ), where r is the modulus and θ is the argument.

The guide provides formulas for converting between Cartesian (x + iy) and polar (r(cos θ + i sin θ)) forms:

  • r = √(x² + y²)
  • tan θ = y/x
  • x = r cos θ
  • y = r sin θ

Example: The guide demonstrates how to express √3 + i in modulus-argument form.

This representation is particularly useful for certain complex number operations and for solving problems involving Argand diagrams Further Maths Exam Questions.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

Sign up to see the content. It's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Introduction to Matrices

This page introduces matrices, a topic that often complements complex numbers in A Level Further Maths.

Definition: A matrix is a rectangular array of numbers arranged in rows and columns.

The guide covers basic matrix operations:

  1. Matrix addition and subtraction
  2. Scalar multiplication of matrices
  3. Matrix multiplication

Highlight: When multiplying matrices, the number of columns in the first matrix must equal the number of rows in the second matrix.

The page demonstrates how matrices can be used to represent systems of linear equations, providing a link between matrices and other areas of mathematics.

Example: The guide shows how to represent the system of equations s = 3u + 2v and t = 5u + 7v as a matrix equation.

This introduction to matrices lays the groundwork for more advanced topics in linear algebra and is essential for solving complex problems in A level further maths quadratic equations.

Complex Numbers:
N
Z NOR
Natural
Integers
Rational
Real
Solutions...
x = 1 - 3
x + 2 = 3
x + 2 = 1
2x = 3
x² = 2
x² = - 4
⇒ x = ± √√-4
⇒x=±

Sign up to see the content. It's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Advanced Matrix Operations

This final page covers more advanced matrix operations, building on the foundations laid in the previous section.

The guide introduces the concept of matrix transposition:

Definition: The transpose of a matrix is obtained by interchanging its rows and columns.

The page provides examples of transposing matrices and explains the significance of the leading diagonal in this operation.

The guide also covers multiplication of matrices with different dimensions, demonstrating the process step-by-step:

Example: The multiplication of a 2x3 matrix by a 3x2 matrix is shown in detail.

These advanced matrix operations are crucial for solving complex problems in linear algebra and are often applied in various areas of A Level Further Maths.

This comprehensive guide serves as an excellent resource for students preparing for exams and seeking to master complex numbers and matrices in A Level maths complex numbers.

Can't find what you're looking for? Explore other subjects.

Knowunity is the #1 education app in five European countries

Knowunity has been named a featured story on Apple and has regularly topped the app store charts in the education category in Germany, Italy, Poland, Switzerland, and the United Kingdom. Join Knowunity today and help millions of students around the world.

Ranked #1 Education App

Download in

Google Play

Download in

App Store

Knowunity is the #1 education app in five European countries

4.9+

Average app rating

13 M

Pupils love Knowunity

#1

In education app charts in 12 countries

950 K+

Students have uploaded notes

Still not convinced? See what other students are saying...

iOS User

I love this app so much, I also use it daily. I recommend Knowunity to everyone!!! I went from a D to an A with it :D

Philip, iOS User

The app is very simple and well designed. So far I have always found everything I was looking for :D

Lena, iOS user

I love this app ❤️ I actually use it every time I study.