Complex numbers

Arithmetic with i, and quadratics whose solutions are not real.

Standards:N-CN.A.1N-CN.A.2N-CN.C.7

Try it: three questions

Real questions from the practice bank. Tap an answer to check it.

Question 1 of 3

If z = 3 + 4i, find |z| (the modulus of z).

Question 2 of 3

Find the product of the complex numbers (2 + 3i) and (1 − i).

Question 3 of 3

Find the modulus (absolute value) of the complex number z = 3 − 4i.

How this fits in

Complex numbers is one skill in the Advanced Algebra unit. Students read the unit lesson, then earn a bronze, silver, or gold medal on their last 10 answers. Medals never go down. A mastered unit comes back for review after 1, 3, 7, 16, and 35 days so it stays learned.

Polynomial operations and long division
The remainder and factor theorems
Rational expressions
Rational equations
Radical expressions and rational exponents
Radical equations
Exponential growth and decay
Logarithms and logarithmic equations
Function composition and inverses

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