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NRICH topics: Place value and the number system Complex numbers

Resources tagged with: Complex numbers

Content type:
Age range:
Challenge level:

There are 22 NRICH Mathematical resources connected to Complex numbers, you may find related items under Place value and the number system.

Broad Topics > Place value and the number system > Complex numbers

Problem Primary curriculum Secondary curriculum

Complex Partial Fractions

To break down an algebraic fraction into partial fractions in which all the denominators are linear and all the numerators are constants you sometimes need complex numbers.

Age 16 to 18
Challenge Level Yellow starYellow star
Problem Primary curriculum Secondary curriculum

Three by One

There are many different methods to solve this geometrical problem - how many can you find?

Age 16 to 18
Challenge Level Yellow star
Problem Primary curriculum Secondary curriculum

8 Methods for Three by One

This problem in geometry has been solved in no less than EIGHT ways by a pair of students. How would you solve it? How many of their solutions can you follow? How are they the same or different? Which do you like best?

Age 14 to 18
Challenge Level Yellow starYellow star
List Primary curriculum Secondary curriculum

Adventures with Complex Numbers

This collection is designed to give an introductory taste of complex numbers.

Age 14 to 18
Challenge Level Yellow star
Problem Primary curriculum Secondary curriculum

Strolling Along

What happens when we multiply a complex number by a real or an imaginary number?

Age 14 to 18
Challenge Level Yellow star
Problem Primary curriculum Secondary curriculum

Opening the Door

What happens when we add together two complex numbers?

Age 14 to 18
Challenge Level Yellow star
Problem Primary curriculum Secondary curriculum

Sheep in Wolf's Clothing

Can you work out what simple structures have been dressed up in these advanced mathematical representations?

Age 16 to 18
Challenge Level Yellow starYellow starYellow star
Problem Primary curriculum Secondary curriculum

Impedance Can Be Complex!

Put your complex numbers and calculus to the test with this impedance calculation.

Age 16 to 18
Challenge Level Yellow starYellow starYellow star
Problem Primary curriculum Secondary curriculum

Pumping the Power

What is an AC voltage? How much power does an AC power source supply?

Age 16 to 18
Challenge Level Yellow starYellow star
Article Primary curriculum Secondary curriculum

What Are Numbers?

Ranging from kindergarten mathematics to the fringe of research this informal article paints the big picture of number in a non technical way suitable for primary teachers and older students.

Age 7 to 18
Problem Live Primary curriculum Secondary curriculum

Two and Four Dimensional Numbers

Matrices and Complex Numbers combine to enable us to create four dimensional numbers.

Age 16 to 18
Challenge Level Yellow star
Problem Primary curriculum Secondary curriculum

Sextet

Investigate x to the power n plus 1 over x to the power n when x plus 1 over x equals 1.

Age 16 to 18
Challenge Level Yellow star
Problem Primary curriculum Secondary curriculum

Footprints

Make a footprint pattern using only reflections.

Age 16 to 18
Challenge Level Yellow starYellow star
Article Primary curriculum Secondary curriculum

What Are Complex Numbers?

This article introduces complex numbers, brings together into one bigger 'picture' some closely related elementary ideas like vectors and the exponential and trigonometric functions and their derivatives and proves that e^(i pi)= -1.

Age 16 to 18
Problem Primary curriculum Secondary curriculum

Complex Sine

Solve the equation sin z = 2 for complex z. You only need the formula you are given for sin z in terms of the exponential function, and to solve a quadratic equation and use the logarithmic function.

Age 16 to 18
Challenge Level Yellow starYellow starYellow star
Problem Primary curriculum Secondary curriculum

Thousand Words

Here the diagram says it all. Can you find the diagram?

Age 16 to 18
Challenge Level Yellow starYellow starYellow star
Problem Primary curriculum Secondary curriculum

Cube Roots

Evaluate without a calculator: (5 sqrt2 + 7)^{1/3} - (5 sqrt2 - 7)^1/3}.

Age 16 to 18
Challenge Level Yellow starYellow starYellow star
Problem Primary curriculum Secondary curriculum

Napoleon's Theorem

Triangle ABC has equilateral triangles drawn on its edges. Points P, Q and R are the centres of the equilateral triangles. What can you prove about the triangle PQR?

Age 14 to 18
Challenge Level Yellow starYellow starYellow star
Problem Primary curriculum Secondary curriculum

Complex Rotations

Choose some complex numbers and mark them by points on a graph. Multiply your numbers by i once, twice, three times, four times, ..., n times? What happens?

Age 16 to 18
Challenge Level Yellow starYellow star
Article Primary curriculum Secondary curriculum

An Introduction to Complex Numbers

A short introduction to complex numbers written primarily for students aged 14 to 19.

Age 16 to 18
Problem Primary curriculum Secondary curriculum

Target Six

Show that x = 1 is a solution of the equation x^(3/2) - 8x^(-3/2) = 7 and find all other solutions.

Age 16 to 18
Challenge Level Yellow starYellow starYellow star
Problem Primary curriculum Secondary curriculum

Roots and Coefficients

If xyz = 1 and x+y+z =1/x + 1/y + 1/z show that at least one of these numbers must be 1. Now for the complexity! When are the other numbers real and when are they complex?

Age 16 to 18
Challenge Level Yellow star

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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