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Andrew Marr's History: SurvivalSaturday, 25th April 2015 10:00 - YesterdayAndrew Marr sets off on an epic journey through 70,000 years of human history, starting with our earliest beginnings... Read more: OU on the BBC: Andrew Marr's History of the World - Survival
Andrew Marr's History: SurvivalSaturday, 25th April 2015 16:00 - Yesterday
Thinking Allowed: The Ethnography Award winner 2015Monday, 27th April 2015 00:15 - BBC Four
Christopher Plummer on King LearTuesday, 28th April 2015 04:35 - Sky Arts 1
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Thinking Allowed: The Ethnography Award 'Shortlist' 2015Available until Friday, 15th April 2016 10:30
A History of Ideas - Descartes Cogito Ergo SumAvailable until Thursday, 14th April 2016 08:30
OU on the BBC: Andrew Marr's History of the World - SurvivalAndrew Marr sets off on an epic journey through 70,000 years of human history, starting with our... Read more: OU on the BBC: Andrew Marr's History of the World - Survival
Take the photographic memory testCan you capture scenes just by looking at them? Find out with our photographic memory test. Launch now: Take the photographic memory test
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An introduction to complex numbers
This unit looks at complex numbers. You will learn how they are defined, examine their...
This unit looks at complex numbers. You will learn how they are defined, examine their geometric representation and then move on to looking at the methods for finding the nth roots of complex numbers and the solutions to simple polynominal equations.
After studying this unit you should:
- be able to perform basic algebraic manipulation with complex numbers;
- understand the geometric interpretation of complex numbers;
- know methods of finding the nth roots of complex numbers and the solutions of simple polynomial equations.
An introduction to complex numbers
This unit is an adapted extract from the Open University course
This unit is devoted solely to complex numbers.
In Section 1, we define complex numbers and show you how to manipulate them, stressing the similarities with the manipulation of real numbers.
Section 2 is devoted to the geometric representation of complex numbers. You will find that this is very useful in understanding the arithmetic properties introduced in Section 1.
In Section 3 we discuss methods of finding nth roots of complex numbers and the solutions of simple polynomial equations.
The final two sections deal with inequalities between real-valued expressions involving complex numbers. First we use inequalities in Section 4 to describe various subsets of the complex plane. Then we show, in Section 5, how to prove such inequalities. In particular, we introduce the Triangle Inequality, which can be used to obtain an estimate for the size of a given complex expression.