What is a complex number?

A complex number is one that is made up of a complex and real part, they can all be written as:

a+bi, where a and b are real numbers.

The thing that makes the number "complex" is "i", the imaginary number. "i" is the square root of -1, so if you had "square root of -4" your answer would be "root 4 times by i" or "2i".

It has many applications, particularly in Pure Mathematics.

James B. A Level Maths tutor, GCSE Maths tutor

2 years ago

Answered by James, an A Level Maths tutor with MyTutor

Still stuck? Get one-to-one help from a personally interviewed subject specialist


£20 /hr

Harry C.

Degree: General Engineering (Masters) - Durham University

Subjects offered:Maths, Physics+ 1 more

Further Mathematics

“Second year Engineering student, I'm passionate, dedicated and personable. A- Level Maths and Physics (A*AA).”

MyTutor guarantee

£26 /hr

Mark H.

Degree: Mathematics MMath (Masters) - Manchester University

Subjects offered:Maths, Physics+ 1 more

Further Mathematics

“Hello there, I'm Mark and I study Mathematics at the University of Manchester! Let me help you achieve your best!”

£26 /hr

Michelangelo M.

Degree: MMath Mathematics with Placement (Masters) - Bath University

Subjects offered:Maths, Italian+ 4 more

Further Mathematics

“Mathematics student at the University of Bath, willing to help you love this subject and improve your grades.”

About the author

James B.

Currently unavailable: for regular students

Degree: Mathematics (Masters) - Exeter University

Subjects offered:Maths


“Third Year Mathematics Student and qualified TEFL Tutor, available any time to discuss tuition in either maths or english as a foreign language.”

You may also like...

Posts by James

How do you differentiate X to the power of a?

How to prove that (from i=0 to n)Σi^2= (n/6)(n+1)(2n+1), by induction.

What is "Standard Form"?

What is a complex number?

Other A Level Maths questions

How do I find the maximum/minimum of a function?

Find the equation of the straight line that passes through the points (1,2) and (2,4)

how to integrate by parts

Differentiate: y=12x(2x+1)+1/x

View A Level Maths tutors

We use cookies to improve your site experience. By continuing to use this website, we'll assume that you're OK with this. Dismiss