WEBVTT
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What is the projection of π· on line π΄πΆ?
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When we think about projections, the first thing we wanna identify is our target line, the line on which our projection will fall.
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In this case, thatβs the line π΄πΆ.
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We say that π΄πΆ is our target line, and we want to project the point π· onto this target line.
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To do that, we need to consider a perpendicular line to our target line that intersects the point we want to make a projection of.
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Helpfully, we see here that line segment πΈπ· is perpendicular to the line π΄πΆ.
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If we imagine this perpendicular line as a light source, the projection of π· onto π΄πΆ will be the shadow of π· onto line π΄πΆ.
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And the shadow of this point will be another point.
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In this case, itβs going to be the point πΈ.
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The point πΈ is the place of the intersection of the perpendicular line π·πΈ onto π΄πΆ.
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And so, we can call the point πΈ the projection.