Audio Transcript Auto-generated
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Hello everyone whether it's a good morning a good afternoon.
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We're gonna start off with our lecture on circles.
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Especially looking at there measurements such as the area, the
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circumference. And learn a bit about pie I'm sure many
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of you have heard the word and if you know
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what it is good if you don't we'll go through
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quickly. So I love circles.
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Uh huh.
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Okay so in your circle you have different pieces that
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help us so your diameter because the length from one
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side going through the center to the other so it's
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the distance across the circle through the center.
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Make sure to write these definitions down there.
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Quite useful.
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You have your center is the middle of your circle
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as it sounds and your circumference is the distance all
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the way around the outside of your circle your radius
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is from the center to the side so it's half
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your diameter.
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Okay have a look at these pictures.
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What is the first circle on your left?
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What's that depicting?
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Its your diameter?
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The r.
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Is depicting a radius and the third one is a
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bit of a question because it's only showing you our
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center. It's actually just a weird segment of the circle
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that's not your diameter because it's not going through the
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center. Now let's introduce pie quickly.
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I'll go through a nice demonstration just now.
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But pie is actually your circumference divided by your diameter.
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So no matter what size your circle is if you
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take the circumference and your divided by the diameter.
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You're gonna get pie aroma or circumference, the outside length
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of your circle.
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So if you have defense around a circle, it's going
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to be that outside.
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And if we divided by The distance from the two
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sides that go through the center is going to give
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you pie, pie is generally about 3.14.
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It carries on going forever and ever.
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And it's a really interesting number.
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Um, but yes, that's your relationship between pie.
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Let's dive into a nice demonstration.