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Unemployment Rate Primer, Current Economics, Finance and Capital Markets
Ever wonder how the Bureau of Labor Statistics calculates the ever-changing unemployment rate? Sal explains this by breaking down the US population into subsets, including the labor force and the unemployed. He explains the formula for...
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Two Passing Bicycles Word Problem
In this video, Sal solves a word problem sent in by a listener with two cyclists riding towards each other over a given time. It is an interesting problem regarding ratios and the relationship between distance, rate, and time. He shows...
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Trigonometry Word Problems (Part 1)
Sal starts to solve a trigonometric word problem of a wayward ship captain who veers off course and once aware of his predicament, needs to know how far he is from his destination. Instead of using the Law of Cosines in his solution, Sal...
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Trigonometric System Example, Trig Identities and Examples, Trigonometry
Sal solves a challenging problem that consists of a system of three trigonometric equations and three unknowns.
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Trig Identities Part 2 (Part 4 If You Watch the Proofs)
In this video, Sal reviews the basic trigonometric definitions and identities, including the sum of angle formulas, and then derives the double angle formulas.
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Triangle Medians and Centroids, Special Properties and Parts of Triangles, Geometry
This video discusses the terminology used in geometry, including words such as centroid and median. Through this lecture, young mathematicians can see a visual representation of both. The video also demonstrates how to calculate medians.
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Triangle Medians and Centroids (2D Proof), Geometry
In the first part of this series, the instructor addressed the terminology used with medians and centroids of triangles and then showed how to solve this type of problem. He illustrated the concepts using a high-level problem, likely...
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The Mohorovicic Seismic Discontinuity, Cosmology and Astronomy
The phenomena observed in the behavior of waves and data received from seismographs can lead us to various conclusions about the densities of material waves passing through.
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The Angle Game, Angles and Intersecting Lines, Geometry
A motivating activity is coupled with the use of algebra to explore the process of identifying the value of an angle. It feels like magic when Sal shows the solution to the final problem. Also, it would be worthwhile to consider using...
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Testing If a Relationship is a Function, Functions and Their Graphs, Algebra II
This short video looks at different points on a coordinate plane and answers a question about whether these points could represent a function. The answer is determined by looking at each point individually to determine whether, given a...
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Taking Percentages, Linear Equations, Algebra I
There are two percentage concepts covered in an informative video. The first is how to find a given percent of a given number; the second concept shows learners how to find a number when the percent is given. Sal finishes by...
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Challenge Example: Sum of Integers, Linear Equations, Algebra I
The sum of three consecutive odd integers is 231. What is the largest integer? See how to unpack this word problem, set up an equation, and solve for the variable.
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Solving for F in Terms of C, Linear Equations, Algebra I
The instructor uses the temperature formula to illustrate how the variables can be manipulated to solve a problem.
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Solving Equations with the Distributive Property, Linear Equations, Algebra I
Here is an equation in which the first step is to use the distributive property to remove the parenthesis. Then, it is solved for the variables. Since variables are on both sides of the equation, it is important to verify the answer by...
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Example 2: Variables on Both Sides, Linear Equations, Algebra I
Sal offers an example of manipulating numbers on either side of the equal sign to isolate the variable and solve the equation.
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Example: Two-Step Equation with Numerator , Linear Equations, Algebra I
Sal demonstrates how to solve an equation. He begins by saying that the variable needs to be isolated. Then, he shows how to move numbers on either side of the equal sign to isolate the variable. Finally, he verifies answers by plugging...
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Solving a Quadratic by Factoring, Quadratic Equations, Algebra I
The central concept in this video is solving quadratics by factoring. Several examples are shown with positive and negative numbers. The instructor demonstrates setting the factored equation to zero to solve the quadratic, using a graph...
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Slope and Y-Intercept Intuition
The instructor uses a computer graphing program to illustrate how a line changes slope by manipulating the slope values in the equation. He also manipulates the y-intercept value to see where the line crosses the y-axis.
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Slope and Rate of Change, Graphing Lines and Slope, Algebra Basics
Introducing slope as "a way of measuring the inclination of a line," Sal endeavors to provide a working knowledge of slope problems and problem-solving. The video is framed as a review but could be a good way to fill any holes in...
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How to Solve equations of the Form ax = b, Linear Equations, Algebra I
Sal dissects basic algebraic equations of the form Ax=B. He encourages viewers to fully understand the equations before learning how to manipulate them. Furthermore, he teaches students how to solve the equations systematically. The...
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Similar Triangles (Part 2), Similarity, Geometry
Building on concepts in the first part of the series on similar triangles, installment number two explores how to find the values for given angles in a triangle. These problems are solved by using algebra and ratios. A step-by-step...
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Scientific Notation Examples, Pre-Algebra
This video contains additional scientific notation examples, continuing from the previous presentation. Viewers can see Sal work through several more problems using the techniques he has outlined throughout the pre-algebra video series.
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Rhombus Diagonals, Quadrilaterals, Geometry
Delving into proof that the diagonals of a rhombus are perpendicular to each other, this lecture evaluates the angles and sides of this figure. It would serve as a great test preparation activity.
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Refraction of Seismic Waves, Cosmology & Astronomy
Mr. Khan uses the metaphor of a car to help explain the change in the direction of waves as they hit a boundary between two mediums. He then goes on to explain the relationship between the earth's structure and density and the waves'...