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## This page provides a list of educational videos related to Divide by 9 and 10. You can also use this page to find sample questions, apps, worksheets, lessons , infographics and presentations related to Divide by 9 and 10.

# Complex Numbers In Polar Form De Moivre's Theorem, Products, Quotients, Powers, and nth Roots Prec

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By The Organic Chemistry Tutor

This precalculus video tutorial focuses on complex numbers in polar form and de moivre's theorem. It explains how to find the products, quotients, powers and nth roots of complex numbers in polar form as well as converting it to and from rectangular form. This video contains plenty of examples and practice problems and is useful for high school and college students taking precalculus or trigonometry. Here is a list of topics: 1. Graphing / Plotting Complex Numbers in a Complex Plane 2. Real Axis vs Imaginary Axis 3. How To Find The Absolute Value of a Complex Number 4. Complex Numbers - Rectangular Form to Polar Form 5. Converting Complex Numbers in Polar Form To Rectangular Form 6. Complex Numbers - List of Equations and Formulas 7. Finding R and Angle Theta From a and b 8. Writing Complex Numbers In Rectangular Form 9. Product of Two Complex Numbers In Polar Form Equation 10. Quotient of Two Complex Numbers In Polar Form Formula 11. Finding Products of Complex Numbers in Polar Form 12. Finding Quotients of Complex Numbers in Polar Form 13. Powers of Complex Numbers in Polar Form 14. De Moivre's Theorem - Roots of Complex Numbers in Polar Form 15. Solving Equations With Complex Numbers 16. Adding Complex Numbers in Polar Form 17. Multiplying Complex Numbers in Polar Form 18. Dividing Complex Numbers in Polar Form

**In this video**

# 3rd Grade Math Rap

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By McCarthy Math Academy

With a little help from the group, Mindless Behavior, I have created a math video with lyrics to help my students to understand and apply core math skills for third grade. People of all ages can jam out to this one. Enjoy!

I've got a case of the operation blues.

Because I don't know which one I should use.

Look at the word problem for the clues.

The key words tell you how to choose.

Each means you multiply or you must divide.

Tryna find the total? Then you multiply

Total's in the problem? Then you must divide.

Not quick to solve it, draw it, get it right.

Addition's easy for me and you

Sum, In all, together, and total too.

When do you subtract? How many more?

Fewer? Left? Less? Difference in a score?

Place value's next. Disco on the " dess "

Ones, tens, hundreds, to the left

Thousands, Ten thousands, hundred...thousand

Say the name of the place, yeah.

The value's the amount of the place

For example, 2,060.

The value of the 2 is 2-0-0-0,

The value of the 6 is 6-0.

When you round, find and underline the place

Spotlight to the right, decide the digit's fate

5 or more, add 1 to the rounding place

4 or less, do nothing but walk away, (estimate)

A pen, penny is one, one cent

A Nic-kel is five, a dime is ten cents

25 for a quarter, George Washington

100 cents makes a dollar, there he goes again.

For pictographs, you gotta check out the key

One smiley face might really equal three

For bar graphs, pay attention to the scale

Think it's counting by ones, huh, you'll fail

Fractions are easy, just draw your best.

Here they go from least to greatest

1/12, 1/6, Â¼, 1/3,

Â½, 2/3, Â¾, Fraction nerd!

You see that number on top,

That's called the numerator

It describes the amount

That is being considered

And if you jump down from the fraction bar

Denominator

It's the total number of equal parts.

Let me give you an example:

Leslie Moin has some coins

A total of 9

2 happen to be pennies

While 7 are dimes.

What's the fraction of dimes?

How many coins? 9

How many dimes? 7

Say the fraction -- seven ninths

Length times width is Area

Distance around is Perimeter

Break down the GEOMETRY

3 sides makes triangle

4 sides = quadrilateral

5 pentagon, 6 hexagon

8 octagon, 10 decagon

Lines that never cross - PARALLEL

Lines that meet or cross - INTERSECTING

Lines that form right angles -- PERPENDICULAR

Same shape, same size -- CONGRUENT

Line that cuts in half - SYMMETRY

Up and Down - VERTICAL

Left to Right -- HORIZONTAL

An angle less than right - ACUTE

An angle opened wide - OBTUSE

Ninety degrees square corner - RIGHT ANGLE

Back to triangles

3 sides the same = equilateral

2 sides the same = isosceles

no sides the same = Hey, that's a scalene right!

So, that's it.

That's our math song.

Before we leave,

Remember to read

Your math problems three times before you answer.

That way you know what the problem

Is asking you to do.

Don't be lazy, be brilliant.

Piece! Like a fraction.

**In this video**

# ALL OF GRADE 9 MATH IN 60 MINUTES!!! (exam review part 1)

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By Lumos Learning

Here is a great exam review video reviewing all of the main concepts you would have learned in the MPM1D grade 9 academic math course. The video is divided in to 3 parts. This is part 1: Algebra. The main topics in this section are exponent laws, polynomials, distributive property, and solving first degree equations. Please watch part 2 and 3 for a review of linear relations and geometry. If you watch all 3 parts, you will have reviewed all of grade 9 math in 60 minutes. Enjoy! Visit jensenmath.ca for more videos and course materials.

**In this video**

# 2011 Roundtable at Stanford: Redefining K-12 Education in America

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By Lumos Learning

October 22, 2011 - Designing an education that truly builds the necessary skills for today's enormously diverse student population is not easy. But it's the key to opportunity for our citizens, economic vitality for our nation, and to assuring the U.S. remains a world leader. There is hope: innovations and innovators that challenge the status quo; research to help us understand how to move the education needle; a virtual army of reformers experimenting with new ways to teach, learn, and run our public schools.

**In this video**