Complex Numbers Flashcards
1
Q
How do you multiply complex numbers?
A
Expand brackets
2
Q
What is i^2 equal to?
A
-1
3
Q
How to divide 2 complex numbers?
A
Multiply numerator and denominator by denominator but with complex number sign switched
4
Q
What to do with a complex number with a line on top of letter?
A
Reverse the sign of the complex number, but not the real number
5
Q
z = 3 + 4i
Find modulus of z
A
sqrt of z^2
= sqrt 9+16
= 5
5
Q
Are imaginary numbers on the y or x axis?
A
Imaginary - y axis
Real - x axis
6
Q
How to write in exponential form
A
re^iθ
where r is the modulus
and θ is the principal argument
7
Q
How to write in polar form?
A
r(cosθ + isinθ)
