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Solving Quadratic Equations by Square Roots, Algebra II
Introducing square roots into the quadratic equation mix, Sal addresses the ways viewers might solve the problems, both correctly and incorrectly. The video is an integral step in not only Sal's algebra series but also in developing math...
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Banking 6: Bank Notes And Checks
Why carry around a heavy suitcase full of gold when you can write a check to your neighbor in the village? Sal's village banks flourish in this video, which introduces checks and demonstrates how they work. While this video is helpful...
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Introduction to Geometric Sequences, Sequences, Series and Induction, Precalculus
This video introduces geometric sequences as "a special sequence of numbers where each successive number is a fixed multiple of the number before it." Sal works slowly in the beginning but picks up the pace as he solves word problems...
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Unit Conversion Word Problem: Drug Dosage, Introduction to Algebra, Algebra I
This video focuses on an example of unit conversion using drug dosage. Sal, the all-knowing pre-algebra guide, uses a problem from a nursing class to show the process of unit conversion within an algebraic expression. This helpful video...
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Introduction to Special Products of Binomials, Algebra I
First, clarifying that people need to "resist every temptation on earth" when squaring a binomial, Sal walks viewers through a few binomial equations using binomials and applies the skills from the previous videos about working with...
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Multiplying and Dividing with Inequalities, Linear Inequalities, Algebra I
Things get a little more complicated in this video, which features Sal solving several inequality problems involving multiplying and dividing by positive and negative numbers. Additionally, he uses a few more kinds of notation to...
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Organic Chemistry Naming Examples 2, Organic Chemistry
Sal continues to work through examples of more complicated carbon chains in this second video of five.
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Ratio And Proportion
Both intuitive and logistical steps bring Sal and the viewers to the correct answers in these problems using ratio and proportion. An equation with ratios introduces the video, and the skills from that problem lend well to the word...
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SAT Prep: Test 5 Section 7 Part 3
The most helpful part of this video is at the very end, when Sal demonstrates how to solve a combinations problem incorrectly (after initially finding the correct answer). The trial-and-error strategy of solving multiple-choice math...
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Aromatic Compounds and Huckel's Rule
Sal gives a good recap of the pi electron behavior in aromatic compounds originating from a benzene ring. He diagrams the hybridization leading to a conjugated system of pi electrons and compares their stability.
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Amine in Sn2 Part 2
An advanced chemistry class will understand Sal's reaction and see his logic in explaining the equilibrium. The levels of electronegativity and likelihood of a nucleophilic attack are balanced and presented in the equation. This is an...
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Square Roots And Real Numbers, Pre-Algebra
Sal works through several problems involving rational and irrational numbers and shows how to find the difference. This video is a good stepping stone for those preparing to take on more challenging algebra work.
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How to Rationalize a Denominator, Exponent Expressions and Equations, Algebra I
"Sal, why do we care? Why must we rationalize denominators?" Acknowledging these (possibly pleading) concerns, Sal explains the reasons behind rationalizing a denominator before demonstrating how to do it several times. Though he admits...
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Banking 17: What Happened to the gold?
Learn the value of a dollar in this video, which explains the natural transition from the gold standard. Asking viewers if they would trust gold or the U.S. Government, Sal explains how the concept of wealth has shifted and adapted...
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SAT Prep: Test 5 Section 7 Part 6
Give your students the edge on their upcoming SAT with this video, which covers algebraic and linear equations. Math students who have a hard time transitioning between skills would benefit from seeing Sal do so.
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Standard Form for Linear Equations
Illuminate the world of mathematics for your class, specifically, the process of linear equations. In this video, Sal teaches about linear equations in standard form after two videos on slope-intercept and slope-point forms. He defines...
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Factoring Special Products, Polynomial and Rational Functions, Algebra II
"Just to get the point drilled into your head," Sal continues his lecture on factoring quadratic expressions, focusing on special products. He works to instill the problem-solving skills necessary to factor in equations quickly and...
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Modeling with Linear Equations Example 2
Sal takes your class’s newfound (or growing) knowledge of graphs of lines to the next level. He presents a few word problems that mathematicians must understand to use linear function graphs.
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SAT Prep: Test 5 Section 3 Part 2
Going over the last problem from the previous video (problem 5), Sal explains his thought process more carefully. Additionally, he solves problems involving measuring angles, algebraic expressions, and averages.
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SAT Prep: Test 5 Section 3 Part 1
Sal starts a new set of practice SAT problems in this video, starting on page 652 of The Official SAT Study Guide. Problems involve fractions and ratios, simplifying equations, and finding the perimeter of given coordinates on a plane.
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SAT Prep: Test 4 Section 8 Part 2
Young mathematicians will appreciate Sal's careful - yet efficient - methods for solving these typical SAT problems. He takes care to explain problems 8-12, but gets cut off in the middle of problem 12 (to be continues in the next video).
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SAT Prep: Test 2 Section 6 Part 2
Reviewing the last problem from the previous video because he feels that he "rushed it," Sal again explains the concept of ratios as it applies to problem 6 on the practice SAT (page 472 in The Official SAT Study Guide). Additional...
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SAT Prep: Test 2 Section 3 Part 1
Page 459 of The Official SAT Study Guide by The College Board features another set of practice SAT math problems, beginning with problems 1-4. Sal demonstrates how to solve problems with factoring and visualization.
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SAT Prep: Test 7 Section 5 Part 3
Choosing the "quick and dirty" method of solving problems rather than more mathematically complicated, Sal shows students the importance of time management when taking the SAT (or other math tests). He still arrives at correct answers,...