Home > Subjects > Mathematics > Level 3 - calculus > 3.4 Complex numbers (AS90638) > Achievement criteria
- Subject: Mathematics
- AS: 90638
- Level: 3
- Credits: 5
- External
Calculus 3.4 Manipulate real and complex numbers, and solve equations
Achievement criteria
The level of achievement that you reach is decided by the questions that you answer correctly.
Achievement
- You manipulate real and complex numbers, and solve equations.
- Manipulation will be based on a selection from:
- conversion between polar and rectangular forms of real and complex numbers
- simplification of sums, differences, products, and quotients of surds or complex numbers expressed in rectangular form
- simplification of products or quotients of complex numbers expressed in polar form
- use of de Moivre’s theorem in the simplification of expressions such as
.
- Equations will be based on a selection from:
- quadratic
- cubic (limited to rational roots only)
- exponential, such as 23x+1=5
- logarithmic, such as ln(x + 5) = 1.34 (any base).
- You are expected to have a knowledge of:
- the remainder and factor theorem
- the process of completing the square.
Achievement with Merit
- You need to reach Achievement.
- You solve more complicated equations which are based on a selection of those equations identified for achievement, plus:
- irrational equations, such as

- cubic equations with one integer root and two complex roots
- equations of the form
, zn = a + bi where a, b are real and n is a positive integer.
- irrational equations, such as
Achievement with Excellence
- You need to reach Achievement with Merit.
- You solve problem(s) involving real or complex numbers that may require a chain of reasoning.
- Problems may include:
- algebraic proofs
- loci – geometric representation of complex numbers
- multi-step equations
- binomial expansions for small positive integer exponents.

