Area of a circle, how to get the formula.
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@sagor122 Pi is defined as the circumference divided by the diameter. The diameter is two times the radius.
therefore: C = 2πr
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There's a simpler explanation. The area of a regular polygon is 1/2 apothem * perimeter.
Think of a circle as a polygon with an infinite number of sides. Perimeter = circumference. C = 2πr. The apothem = r. area = 1/2 2πr *r
simplified:
area = πr^2
If you don't understand the area formula for a regular polygon read this:
Any regular n-gon can be broken into n triangles with the apothem as their height. The base of the triangles is the perimeter, so you end up with 1/2 aP.
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awesome i love pi
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Ms.Kronish showed you this video didn't she? I know she did
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Why is the base 1/2 the circumference?
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WOW
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i want to know why circumference = 2.pie.r,,,,,,,,,ty
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nice
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great man
u solved my project of maths !!
thanzz a lot
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Cool thank you
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Excellent job. I use to have to show my middle-schoolers this with unit pieces that I made. Now, all I have to do is show your video. It's a sign of the times.
Thanks!!!!!
ncbasspraise 10 months ago 4
@ncbasspraise Nice! Let me know if they like it.
mathematicsonline 10 months ago 3