Curated OER
Law of Sines and Law of Cosines
For this Pre-calculus/Trigonometry worksheet, students use the laws of sines and cosines to solve triangles. The four page worksheet contains thirteen problems. Answers are not included.
Khan Academy
Khan Academy: Factor Polynomials: Complex Numbers
Identify correctly factored forms of given polynomials. Factorizations may use complex numbers. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Khan Academy
Khan Academy: Multiply & Divide Complex Numbers in Polar Form
Given two complex numbers in polar form, find their product or quotient. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Khan Academy
Khan Academy: Midpoint of Complex Numbers
Given two complex numbers (either algebraically or graphically), find their midpoint. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Khan Academy
Khan Academy: Complex Numbers From Absolute Value & Angle
Given the absolute value and the angle of a complex number, express the number in the form a+bi. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Khan Academy
Khan Academy: Graphically Add and Subtract Complex Numbers
Add or subtract complex numbers, and plot the result in the complex plane. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Khan Academy
Khan Academy: Distance of Complex Numbers
Given two complex numbers (either algebraically or graphically), find their distance. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Khan Academy
Khan Academy: Powers of Complex Numbers
Simplify a power of a complex number z^n, or solve an equation of the form z^n=k. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Larson Texts
Larson Precalculus: Operations of Complex Numbers in the Complex Plane [Pdf]
A 3-page handout with examples and exercises in adding, subtracting, and multiplying complex numbers in the complex plane, as well as finding complex conjugates.
Khan Academy
Khan Academy: Absolute Value of Complex Numbers
Given a complex number in the form a+bi, find its absolute value. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints. HSN.CN.B.4
Khan Academy
Khan Academy: Angle of Complex Numbers
Given a complex number of the form a+bi, find its angle. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Windstream
Ojk's Precalculus Study Page: Powers of Complex Numbers
An introduction to DeMoivre's Theorem for quickly finding the powers of complex numbers. Assumes knowledge of polar form of complex numbers. Includes several examples and pictures.
Khan Academy
Khan Academy: Polar and Rectangular Forms of Complex Numbers
Given a complex number in rectangular form, write it in polar form. And given a complex number in polar form, write it in rectangular form. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a...
Khan Academy
Khan Academy: Divide Complex Numbers
Given a complex number division problem, express the result as a complex number of the form a+bi. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Windstream
Ojk's Precalculus Study Page: Geometric Representation of Complex Numbers
An introduction to viewing the complex plane in terms of polar coordinates. Assumes knowledge of the conversion formulas. Includes several examples and pictures.
Khan Academy
Khan Academy: Absolute Value of Complex Numbers
Given a complex number in the form a+bi, find its absolute value.
Windstream
Ojk's Precalculus Study Page: Polar Coordinates and Complex Numbers
An introduction to basic conversion formulas for polar coordinates and complex numbers. Includes several examples.
CK-12 Foundation
Ck 12: Precalculus Concepts 2.0
A complete high school Precalculus Concepts course. Includes 'Related Modalities' for each lesson that teach the same concept in different ways. The text materials follows Algebra II and comes before Calculus or Statistics. The content...
Khan Academy
Khan Academy: Complex Number Conjugates
Given a complex number, find its conjugate or plot it in the complex plane. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Windstream
Ojk's Precalculus Study Page: Polar Coordinates Sample Test
A practice test covering the polar form of complex numbers, including using DeMoivre's Theorem to find powers and roots of complex numbers.
CK-12 Foundation
Ck 12: Analysis: Properties of Logarithms
[Free Registration/Login may be required to access all resource tools.] In this lesson students use properties of logarithms to rewrite and expand/condense. Students examine guided notes, review guided practice, watch instructional...