Complex Numbers 1 (AQA A-Level Further Maths): Flashcards

$i = \sqrt{-1}$

$i^2 = -1$

$\sqrt{-a} = i\sqrt{a}$

$a + bi$ where $a, b \in \mathbb{R}$

$a$

$b$

$a - bi$

$a^2 + b^2$

Multiply numerator and denominator by conjugate

Equate real parts and imaginary parts separately