WEBVTT

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Here is the problem: Find the magnitude and unit vector of ⟨-6, 8⟩.

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Vector magnitude and unit vector using exact components.

3
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Square the components and add them.

4
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Take the square root for the magnitude.

5
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Divide each component by the magnitude for the unit vector.

6
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Check: the unit vector has length 1.

7
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Direction angle from the positive x-axis.

8
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So the answer is |u| equals 10; unit vector û equals ⟨-3 over 5, 4 over 5⟩; direction approximately 126.8698976°.

9
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Vectors are added, subtracted and scaled one component at a time. The magnitude comes from the Pythagorean theorem, and dividing by it gives a unit vector of length 1 pointing the same way.

10
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The unit vector prime s components square and add to 1.