What is a complex number?

A complex number is a number that consists of two parts, a real part, like any number you have been dealing with since you started learning maths, and an imaginary number, often tagged along with a i or a j, for example a+bi. The best way to imagine it is as a vector on a plane, the point not unlike one on a x,y axes but instead on a real, imaginary axes. 

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Related Further Mathematics A Level answers

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