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In the last video,
I realized that I

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made a mistake near the end,
but it's not a good one,

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because I copied down
the wrong number.

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And then that led to
the rest of the problem

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not having the right values.

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We figured out that
the vertical component

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of our velocity
earlier in the video

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is negative 26.03
meters per second.

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But then something
happened in my brain,

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and it became negative 29.03.

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So this is not negative 29.03.

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This is negative 26.03
meters per second.

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So the total velocity, we should
have 26.03 squared over here.

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And then if we evaluate
that-- and I just

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did it on my calculator--
26.03 squared plus 5.61.

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Actually, I did it wrong again.

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So it's 5.21.

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Let me redo it.

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So 26.03 squared plus 5.21
squared under the radical

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gives us 26.55.

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So this right over here should
be 26.55 meters per second.

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So that is the magnitude
of our final velocity.

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So that is the magnitude of
our total final velocity.

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And the angle, since this
is not 29.03, this is 26.03,

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we can say that the tangent
of this angle theta-- this

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is this value right
over here-- is

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equal to the length of this
vector right over here,

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which is the opposite side 26.03
over the length of this vector

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here, which is 5.21.

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Or we could say, if we
take the inverse tangent

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of both sides of
this, that the angle

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is equal to the inverse
tangent or the arctangent,

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of 26.03 over 5.21.

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We have the inverse
tangent of 26.03

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divided by 5.21 gives
us roughly 78.7 degrees.

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So the angle here
is 78.7 degrees.

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And it's below the horizontal.

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So we can say that the vector,
the final velocity vector,

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has a magnitude of
26.55 meters per second

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at a direction of 78.7
degrees below the horizontal.

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So I hope I didn't
confuse you too

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much with that mistake
at the end of that video.