Add, subtract and multiply complex numbers in rectangular form multiply and divide complex unmbers in polar form represent complex numbers on an argand diagram. Mathematical institute, oxford, ox1 2lb, july 2004 abstract this article discusses some introductory ideas associated with complex numbers, their algebra and geometry. An introduction to complex numbers homepages of uvafnwi. In these cases, we call the complex number a pure imaginary number. Modulus of a complex number learning outcomes as a result of studying this topic, students will be able to add and subtract complex numbers and to appreciate that the addition of a complex number to another complex number corresponds to a translation in the plane multiply complex numbers and show that multiplication of a complex. Electrical engineers sometimes write jinstead of i, because they want to reserve i for current, but everybody else thinks thats weird. Set of variable points denoted by zwhich will form an argument of. If we add or subtract a real number and an imaginary number, the result is a complex number. Therefore, ab ab if both a and b are negative real numbers. Next, lets take a look at a complex number that has a zero imaginary part. Further, if any of a and b is zero, then, clearly, ab ab. Traditionally the letters z and w are used to stand for complex numbers.
This includes a look at their importance in solving polynomial equations, how complex numbers add and multiply, and how they can be represented. In this section, we shall develop the algebra of complex numbers. Kumars maths revision further pure 1 complex numbers the edexcel syllabus says that candidates should. In spite of this it turns out to be very useful to assume that there is a number ifor which one has 1 i2.