Core Pure Flashcards
Equation of Circle in Argand Diagram
|z - (a + bi)| = r
Equation of Half Line in Argand Diagram
Arg(z - (a + bi)) = θ
Equation of Perpendicular Bisector in Argand Diagram
|z - (a + bi)| = |z - (c + di)|
Gradient of Half Line: Arg(z) = θ
tan(θ)
How many Radians in one full turn?
2π
Modulus Argument Form
z = r (cosθ + i sinθ)
where r = |z|, θ = Arg(z)
Let z = a + bi,
What is the name and value of z*?
Complex Conjugate
a - bi
Quadratic Formula
(-b ± sqrt(b^2 - 4ac)) / 2a
Let z = a + bi
What are the values of Re(z) and Im(z)?
Re(z) = a Im(z) = b
Let z = a + bi
What is the name and value of |z|?
Modulus, distance from Origin to z
sqrt(a^2 + b^2)
Let z = a + bi
What is the name and value of Arg(z)?
Argument, angle between Real axis and line to z from Origin
tan^-1 (b / a)
What are the values of |z| x |w| and |z| + |w|?
|z| x |w| = |zw|
|z| + |w| = |z| + |w| (doesn’t simplify)
What are the values of Arg(z) x Arg(w) and Arg(z) + Arg(w)?
Arg(z) x Arg(w) = Arg(z) x Arg(w) (doesn’t simplify)
Arg(z) + Arg(w) = Arg(zw)
First step for square rooting a complex number? e.g. 2 + 3i
Set sqrt(2 + 3i) equal to a + bi, 2 + 3i = (a + bi)^2 = a^2 + 2abi + b^2
What translation is represented by:
( 1 a )
( 0 1 )
Shear, x axis fixed, (0, 1) maps to (a, 1)