This test has 9 questions worth 20 points in all. Allow 45 minutes. Show all your work: partial credit is given for correct steps. Write complex numbers in the form a + bi and simplify every power of i. A calculator is not needed.
- Grade: Algebra 2
- Chapter: Real and Complex Numbers
- Common Core: N-RN.A.1, N-RN.A.2, N-CN.A.1, N-CN.A.2
- Time: 45 minutes
- Total: 20 points (Question 1: 2 pts; Question 2: 2 pts; Question 3: 2 pts; Question 4: 2 pts; Question 5: 3 pts; Question 6: 2 pts; Question 7: 3 pts; Question 8: 2 pts; Question 9: 2 pts)
Question 1: Classify marked numbers (2 points)
Two numbers are marked on the number line.
- Is each number rational or irrational? (1 point)
- Name the smallest of these sets that contains each number: natural, integer, rational, irrational. (1 point)
Question 2: Points in the complex plane (2 points)
Write the complex number for each point shown.
- Point M (1 point)
- Point N (1 point)
Question 3: Imaginary unit (2 points)
- Simplify \(\sqrt{-72}\). (1 point)
- Solve \(3x^{2}+48=0\). (1 point)
Question 4: Add and subtract (2 points)
Write each result in the form \(a+bi\).
- \((5-3i)+(-8+7i)\) (1 point)
- \((6+2i)-(9-5i)\) (1 point)
Question 5: Multiply (3 points)
Write each product in the form \(a+bi\).
- \((4-i)(2+3i)\) (1 point)
- \((3+5i)^{2}\) (1 point)
- \((7+2i)(7-2i)\) (1 point)
Question 6: Powers of i (2 points)
Simplify.
- \(i^{38}\) (1 point)
- \(i^{83}\) (1 point)
Question 7: Arrows in the plane (3 points)
The arrows show two complex numbers \(z_1\) and \(z_2\).
- Write \(z_1\) and \(z_2\) in the form \(a+bi\). (1 point)
- Find \(z_1+z_2\). (1 point)
- Find \(z_1-z_2\). (1 point)
Question 8: Check a solution (2 points)
Show that \(2+i\) is a solution of \(x^{2}-4x+5=0\).
Question 9: Find the error (2 points)
Liam writes \((2+3i)(2-3i)=4-9i^{2}=4-9=-5\). Find his mistake and give the correct product.
See every chapter on the Algebra 2 math page.



