Worksheets — Set 11

Algebra II · Honors · Complex numbers (intro)

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

Warm-up

1. (15 + 2i) + (13 − 5i) = ___ 2. (14i)(−1i) = ___ 3. Plot 14 − 3i on the complex plane. ___

_See printable PDF for diagram._

Written practice

1. (14 + 2i) + (12 − 5i) = ___ 2. (13i)(−3i) = ___ 3. Plot 13 − 4i on the complex plane. ___ 4. Multiply: (12 + i)(12 − i) = ___ 5. Solve x² + 15 = 0 in ℂ: x = ___ 6. Real part ___ , imaginary part ___ 7. (17 + 2i) + (15 − 5i) = ___ 8. (16i)(−3i) = ___

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More written practice

1. Plot 16 − 3i on the complex plane. ___ 2. Multiply: (15 + i)(15 − i) = ___ 3. Solve x² + 18 = 0 in ℂ: x = ___ 4. (20 + 2i) + (18 − 5i) = ___ 5. (19i)(−3i) = ___ 6. Plot 19 − 4i on the complex plane. ___

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Patterns and rules

1. (31 + 2i) + (29 − 5i) = ___ 2. (30i)(−2i) = ___ 3. Plot 30 − 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