WEBVTT
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Okay, so we want to figure out if this
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is a right angled triangles. So we need to
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take the dot product between each one of these.
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So the dot product between P and Q is going
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to be two times one. That's negative. Three
6
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times zero. It's negative. Two times negative.
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Four. Okay, After we do this, we
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get negative. Six. So remember, if the
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dot product is zero, then we have a right
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angle, so we don't have a right angle yet
11
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. Let's do P and R. So we've got
12
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one time. Six plus negative. Three times negative
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. Two plus negative. Two times negative. Five
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. Okay, so here we're going to end up
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with six plus six, which is 12 plus 10
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, which is 22. So again, still no
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. Um, right angle. So let's take the
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dot product between p Sorry, Q and R.
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So we got two times six plus zero times negative
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two and then plus negative four times negative five.
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Yeah, And again, we end up with 12
22
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. Plus, uh, I'm sorry. 12 plus
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20. Just 2022. So no right angle.
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So this is no