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Algebra: Graphing Lines 1
Viewers will learn how to graph lines, such as y=2x+1. The instructor emphasizes the relationship between the x and y variables, creates an x/y table, and finally graphs the equation. A total of three examples are given in this video.
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Algebra: Equation of a Line
Given two points on a line, find the value for slope using the rise over run formula. Then, find the y-intercept by plugging one of the point values into the equation of a line. Finally, these values are put into the equation of a line y...
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Age Word Problems 3
This presentation demonstrates how to solve an age word problem. It is worth the time it takes to view it.
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Age Word Problems 2
Here are some more age word problems. The instructor uses a chart again to organize the information given. He works through the problem but ends the video with a solution that appears erroneous but is correct. The answer seems too large...
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Ex 1 Age Word Problem
A few word problems involving age are presented. Starting with a simple problem and progressing to more complicated word problems, Sal uses a chart to organize the information given in the more complicated problem to solve for the variable.
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Acute Right and Obtuse Angles, Angles and Intersecting Lines, Geometry
This resource highlights the basics of working with angles and could provide a sound introductory activity for students who are beginning to learn about angles. Eager mathematicians will be introduced to the terminology associated with...
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Absolute Value Equation Example 2, Linear Equations, Algebra I
Sal demonstrates how to solve an absolute value equation, keeping in mind there are two possible answers.
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30-60-90 Triangles II
This is the fourth video in a series in which the instructor continues a discussion of the Pythagorean theorem. It focuses on calculations involving right triangles with 30—and 60-degree angles.
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Vi and Sal Talk About the Mysteries of Benford's Law, Logarithms, Algebra II
Challenge your students to explain why this interesting mathematical law works! Sal, accompanied by Vi Hart, demonstrates BenfordÕs Law. They challenge the listeners to see if they can give an intuitive reason why this law fairly...
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Vi and Sal Explore How We Think About Scale, Algebra II
Why do people perceive a bigger difference between the numbers one and two than between the numbers 1001 and 1002? In this interesting video, Sal is accompanied by Vi Hart. They talk about how we tend to think according to the...
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Logarithmic Scale, Logarithms, Algebra II
In this thought-provoking video, Sal shows how a typical linear scale is different from a logarithmic scale. He plots numbers on both scales and compares them to show why the logarithmic scale is useful. This video gives an intuitive...
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Introduction to i and Imaginary Numbers, Imaginary and Complex Numbers, Precalculus
Students are always fascinated by imaginary numbers. In this video, Sal defines the imaginary unit, i, and shows when raising i to an exponent, it has a cyclic nature.
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Trig Identities Part 3 (Part 5 If You Watch the Proofs), Trigonometry
Sal takes the mystery out of the trigonometric identities by showing how easily they can be derived. He continues with a problem he started in the video �Trig Identities part three (part five if you watch the proofs) and proves the trig...
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Introduction to the Unit Circle, Trigonometry
In this video, Sal shows how the sine and cosine of an angle are defined on the unit circle. He inscribes a 30-60-90 triangle in the unit circle and explains how to use SOH-CAH-TOA to find the circle's coordinates.
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Find the Volume of a Triangular Prism and Cube, Geometry
By describing the formula used to calculate the volume of a triangular prism, Sal gives students practice in solving volume equations. The questions are straightforward and solved in an easy-to-follow manner. Show this to your class as...
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Limit Examples (Part 1), Limits, Differential Calculus
One example is finding the limit as x approaches -1 of (2x+2)/(x+1), solved by simplifying the expression and then explored intuitively by looking at the left and right-hand limits. The second example of finding the limit as x approaches...
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Multiplying and Dividing Rational Expressions 1, Algebra II
Provide your algebra class with some review of rational expressions in this video. Sal uses several sample problems to show viewers the process, and his explanations are clear and easy to understand.
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Quadratic Equation Part 2, Quadratic Equations, Algebra I
The instructor continues solving quadratic equations by plugging values into the quadratic formula. These examples are more difficult because the answers do not correspond to whole numbers.
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Change of Base Formula Proof, Logarithms, Algebra II
This video proves the helpful change of base formula for logarithms. The proof steps may need to be more intuitive to most logarithm learners, but the algebraic manipulation shown using logs is interesting.
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Complex Numbers (Part 2)
This video continues looking at dividing complex numbers by looking at the conjugate of a complex number. The instructor then uses the conjugate to rationalize the denominator of a rational expression with a complex number in the...
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Functions (Part III)
Sal draws a graphical representation of a function, f(x), and builds and evaluates other functions based on that function.
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Functions (Part 4)
This video explores a listener's example of a function. You are given the composite function and one function, and you must find the other function.
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X- and Y-Intercepts 2, Linear Equations and Functions
Given a linear equation in standard form, find the x-intercept and y-intercept. In this video, Sal shows how to set x = 0 and solve the y-intercept and how to set y = 0 and find the x-intercepts.