WEBVTT

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>> This is an illustration of --
2-2, the second part of lab 2.

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I'm going to start by
creating three circles.

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The circle in the middle

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with center zero comma
3.75 of radius 1.

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And then another
circle at center --

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the coordinates of the
center are 1.5 comma .75.

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That's the lower right
circle of radius .75.

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And then the third circle, 2.5
comma 5.75 of radius 1 as well.

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Then, next I'm going to do,
is I'm going to create a --

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I want to make sure that tangent
is on but not perpendicular.

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So I'm going to make a -- the
line tangent to the circle

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and tangent to the circle.

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Line tangent to the circle.

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And I want to make sure
that perpendicular is on.

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So I say perpendicular
to the line.

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That creates that short
line tangent to the circle

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and perpendicular to the line.

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Next thing I'm going
to do is I'm going

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to turn off perpendicular
again because it gets confused

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between tangent and
perpendicular.

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So I'm going to make it
tangent to this circle.

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And then I want to make sure
it's perpendicular so I have

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to change, again,
to perpendicular.

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That short little line.

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So since the shortest
line is perpendicular

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to the original line and the
third line is perpendicular

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to the short line, the two
long lines are parallel

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to each other.

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Now I'm going to have
to simply extend.

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When you extend, it asks
you for the boundary first

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and then you press enter
in between before you click

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on the line to extend.

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And then, same thing with trim.

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OK? I'm going to use the
boundaries for circle.

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So I click on the circle.

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Then that's the trimming edge

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and then press enter
before clicking on the part

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of the line I want to trim.

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And I'm going to trim again.

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This time, I am going
to trim the circle.

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So the boundary is
those two lines.

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Press enter.

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And then click on the
part of the circle

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that I want to trim away.

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So I'm going to create
a short horizontal line

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on the bottom starting from --
I'm going to turn on the snap

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so I can rely on my snap.

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So from horizontal line, from
the middle, from the original

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to the tangent of
this first line.

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Then I'm going to
trim that circle.

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And then I'm going to mirror all
these line segments and arcs.

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Press enter.

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Then it asks for the
line, mirror line,

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so I select any vertical
line, any vertical line.

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Then it asks, "Do you want
to erase the source object?"

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I don't want to erase,
so I'll say n.

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Then, finally, I
need to trim, again,

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with these two lines
as the boundary.

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Press enter.

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And then trim this away.

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And then I am done.