4th grade math on Khan Academy: 4th grade is the time to start really fine-tuning your arithmetic skills. Not only will you be a multi-digit addition and subtraction rockstar, but you'll extend the multiplication and division that you started in 3rd grade to several digits. You'll also discover that you sometimes have something left over (called a "remainder") when you divide. In 3rd grade you learned what a fraction is. Now you'll start adding, subtracting, multiplying, and comparing them. You'll also see how they relate to decimals. On other fronts, you'll learn how to convert between different units (which is super important when comparing the size and speed of robot unicorns in different countries) and continue your journey thinking about various shapes in two dimensions. Some of the foundational concepts of geometry (like lines, rays and angles) also get introduced. As always, we'll round this out with a healthy dose of applied word problems and explorations of number patterns and properties (including the ideas of factors, multiples and prime numbers). The fun must not stop! (Content was selected for this grade level based on a typical curriculum in the United States.)
More free lessons at: http://www.khanacademy.org/video?v=0DBDuNYsciY
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https://www.youtube.com/watch?v=0DBDuNYsciY
Note: All Khan Academy content is available for free at (www.khanacademy.org)
U08_L2_T3_we1 Multiplying Polynomials 1
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https://www.youtube.com/watch?v=gg6vUnElXqo
Note: All Khan Academy content is available for free at (www.khanacademy.org)
Created by Sal Khan.
View more lessons or practice this subject at https://www.khanacademy.org/humanities/us-government-and-civics/american-civics-parent/american-civics/v/fafsa_intro?utm_source=youtube&utm_medium=desc&utm_campaign=usgovernmentandcivics
Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. We offer quizzes, questions, instructional videos, and articles on a range of academic subjects, including math, biology, chemistry, physics, history, economics, finance, grammar, preschool learning, and more. We provide teachers with tools and data so they can help their students develop the skills, habits, and mindsets for success in school and beyond. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help! Donate or volunteer today!
Donate here: https://www.khanacademy.org/donate?utm_source=youtube&utm_medium=desc
Volunteer here: https://www.khanacademy.org/contribute?utm_source=youtube&utm_medium=desc
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https://www.youtube.com/watch?v=7nKXXKn6jL8
Note: All Khan Academy content is available for free at (www.khanacademy.org)
Remember that what you do to one side, you have to do to the other. Will you multiply or divide both sides to dump the fraction, x/a? Let's do it together.
Practice this lesson yourself on KhanAcademy.org right now:
https://www.khanacademy.org/math/algebra/solving-linear-equations-and-inequalities/equations_beginner/e/linear_equations_1?utm_source=YT&utm_medium=Desc&utm_campaign=AlgebraI
Watch the next lesson: https://www.khanacademy.org/math/algebra/solving-linear-equations-and-inequalities/equations_beginner/v/solving-one-step-equations?utm_source=YT&utm_medium=Desc&utm_campaign=AlgebraI
Missed the previous lesson?
https://www.khanacademy.org/math/algebra/solving-linear-equations-and-inequalities/equations_beginner/v/simple-equations?utm_source=YT&utm_medium=Desc&utm_campaign=AlgebraI
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https://www.youtube.com/watch?v=DqeMQHomwAU
Note: All Khan Academy content is available for free at (www.khanacademy.org)
Let’s explore the meaning and origin of the word “recognition”.
Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now!
https://www.khanacademy.org/ela/new-6th-grade-reading-and-vocabulary/x8ddea1200317e822:what-defines-us/x8ddea1200317e822:determining-author-s-purpose/v/recognition-vocabulary-623a
Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. We offer quizzes, questions, instructional videos, and articles on a range of academic subjects, including math, biology, chemistry, physics, history, economics, finance, grammar, preschool learning, and more. We provide teachers with tools and data so they can help their students develop the skills, habits, and mindsets for success in school and beyond. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help!
Donate or volunteer today! Donate here: https://www.khanacademy.org/donate?utm_source=youtube&utm_medium=desc
Volunteer here: https://www.khanacademy.org/contribute?utm_source=youtube&utm_medium=desc
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https://www.youtube.com/watch?v=6zdkeZ_UDXY
Note: All Khan Academy content is available for free at (www.khanacademy.org)
Another arc length integration example
More free lessons at: http://www.khanacademy.org/video?v=MtRXjXdXDow
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https://www.youtube.com/watch?v=MtRXjXdXDow
Note: All Khan Academy content is available for free at (www.khanacademy.org)
The original draft of the Bill of Rights had twelve amendments, not ten! What were those unadopted amendments? In this video, Kim discusses the unadopted amendments with scholar Fergus Bordewich. To learn more about US Government and Politics, visit Khan Academy at https://www.khanacademy.org/humanities/ap-us-government-and-politics To read more about constitutional law, visit the National Constitution Center’s website: https://constitutioncenter.org On this site, leading scholars interact and explore the Constitution and its history. For each provision of the Constitution, experts from different political perspectives coauthor interpretive explanations when they agree and write separately when their opinions diverge.
View more lessons or practice this subject at https://www.khanacademy.org/humanities/us-government-and-civics/us-gov-the-national-constitution-center/us-gov-the-bill-of-rights-ncc/v/unadopted-amendments?utm_source=youtube&utm_medium=desc&utm_campaign=usgovernmentandcivics
Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. We offer quizzes, questions, instructional videos, and articles on a range of academic subjects, including math, biology, chemistry, physics, history, economics, finance, grammar, preschool learning, and more. We provide teachers with tools and data so they can help their students develop the skills, habits, and mindsets for success in school and beyond. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help! Donate or volunteer today!
Donate here: https://www.khanacademy.org/donate?utm_source=youtube&utm_medium=desc
Volunteer here: https://www.khanacademy.org/contribute?utm_source=youtube&utm_medium=desc
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https://www.youtube.com/watch?v=lTNwCTDokrU
Note: All Khan Academy content is available for free at (www.khanacademy.org)
Introduction to addition. Multiple visual ways to represent addition.
Practice this lesson yourself on KhanAcademy.org right now: https://www.khanacademy.org/e/addition_1?utm_source=YTdescription&utm_medium=YTdescription&utm_campaign=YTdescription
Watch the next lesson: https://www.khanacademy.org/math/arithmetic/addition-subtraction/basic_addition/v/basic-subtraction?utm_source=YT&utm_medium=Desc&utm_campaign=Arithmetic
Arithmetic on Khan Academy: So you're ready to have some arithmetic fun? You've come to the right spot! It's the first "official" math topic and chalked full of fun exercises and great videos which help you start your journey towards math mastery. We'll cover the big ones: addition, subtraction, multiplication, and division, of course. But we don't stop there. We'll get into negative numbers, absolute value, decimals, and fractions, too. Learning math should be fun, and we plan on having some with you. Ready to get started?
About Khan Academy: Khan Academy is a nonprofit with a mission to provide a free, world-class education for anyone, anywhere. We believe learners of all ages should have unlimited access to free educational content they can master at their own pace. We use intelligent software, deep data analytics and intuitive user interfaces to help students and teachers around the world. Our resources cover preschool through early college education, including math, biology, chemistry, physics, economics, finance, history, grammar and more. We offer free personalized SAT test prep in partnership with the test developer, the College Board. Khan Academy has been translated into dozens of languages, and 100 million people use our platform worldwide every year. For more information, visit www.khanacademy.org, join us on Facebook or follow us on Twitter at @khanacademy. And remember, you can learn anything.
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https://www.youtube.com/watch?v=AuX7nPBqDts
Visualizing the Fourier expansion of square wave. A square wave can be approximated by adding odd harmonics of a sine wave.
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https://www.youtube.com/watch?v=aalANrz7bi8
Note: All Khan Academy content is available for free at (www.khanacademy.org)