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Math

Algebra II

Conceptual videos and worked examples from basic algebra through algebra 2. Includes videos from the former algebra worked examples playlists.
Community Questions
A thumbnail for: Systems of equations and inequalities
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Systems of equations and inequalities

What happens when we have many variables but also many constraints.
A thumbnail for: Functions and their graphs
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Functions and their graphs

Revisiting what a function is and how we can define and visualize one.
A thumbnail for: Polynomial and rational functions
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Polynomial and rational functions

Exploring quadratics and higher degree polynomials. Also in-depth look at rational functions.
A thumbnail for: Rational expressions
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Rational expressions

You have probably been wondering whether our powers of algebraic problem solving break down if we divide by the variable or we have entire expressions in denominator of a fraction. Well, they don't! In this topic, you'll learn how to interpret and manipulate rational expressions (when you have one algebraic expression divided by another)!
A thumbnail for: Exponential and logarithmic functions
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Exponential and logarithmic functions

An look at exponential and logarithmic functions including many of their properties and graphs.
A thumbnail for: Logarithms
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Logarithms

Log-a-what? No, this tutorial is about neither chopped wood nor music (actually logarithms do have applications in music), but it is fascinating nonetheless. You know how to take an exponent. Now you can think about what exponent you have to raise a number to to get another number. Yes, I agree--unstoppable fun for the whole family. No, seriously, logarithms are used everywhere (including to measure earthquakes and sound).
A thumbnail for: Imaginary and complex numbers
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Imaginary and complex numbers

Understanding and solving equations with imaginary numbers.
A thumbnail for: Conic sections
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Conic sections

A detailed look at shapes that are prevalent in science: conic sections
A thumbnail for: Matrices
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Matrices

Understanding and solving matrices.
Systems of equations and inequalities
What happens when we have many variables but also many constraints.

Solving systems of equations for the king

Whether in the real world or a cliche fantasy one, systems of equations are key to solving super-important issues like "the make-up of change in a troll's pocket" or "how can order the right amount of potato chips for a King's party." Join us as we cover (and practice with examples and exercises) all of the major ways of solving a system: graphically, elimination, and substitution. This tutorial will also help you think about when system might have no solution or an infinite number of solutions. Very, very exciting stuff!

Systems of inequalities

You feel comfortable with systems of equations, but you begin to realize that the world is not always fair. Not everything is equal! In this short tutorial, we will explore systems of inequalities. We'll graph them. We'll think about whether a point satisfies them. We'll even give you as much practice as you need. All for 3 easy installments of... just kidding, it's free (although the knowledge obtained in priceless). A good deal if we say so ourselves!

Systems with three variables

Two equations with two unknowns not challenging enough for you? How about three equations with three unknowns? Visualizing lines in 2-D too easy? Well, now you're going to visualize intersecting planes in 3-D, baby. (Okay, we admit that it is weird for a website to call you "baby.")