Worksheets — Set 5

Algebra II · Honors · Complex numbers (intro)

Print and write your answers. Use diagrams to show thinking.

Warm-up

1. (9 + 2i) + (7 − 5i) = ___ 2. (8i)(−1i) = ___ 3. Plot 8 − 3i on the complex plane. ___

_See printable PDF for diagram._

Written practice

1. (8 + 2i) + (6 − 5i) = ___ 2. (7i)(−3i) = ___ 3. Plot 7 − 4i on the complex plane. ___ 4. Multiply: (6 + i)(6 − i) = ___ 5. Solve x² + 9 = 0 in ℂ: x = ___ 6. Real part ___ , imaginary part ___ 7. (11 + 2i) + (9 − 5i) = ___ 8. (10i)(−3i) = ___

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More written practice

1. Plot 10 − 3i on the complex plane. ___ 2. Multiply: (9 + i)(9 − i) = ___ 3. Solve x² + 12 = 0 in ℂ: x = ___ 4. (14 + 2i) + (12 − 5i) = ___ 5. (13i)(−3i) = ___ 6. Plot 13 − 4i on the complex plane. ___

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Patterns and rules

1. (25 + 2i) + (23 − 5i) = ___ 2. (24i)(−2i) = ___ 3. Plot 24 − 3i on the complex plane. ___

_See printable PDF for diagram._

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Parent tip: Combine like terms: real with real, imaginary with imaginary