# Example calcuating magnitude of vector from graph | Summary and Q&A

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January 7, 2016
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Example calcuating magnitude of vector from graph

## TL;DR

The video explains how to calculate the magnitude of a vector using the distance formula and the Pythagorean theorem.

## Key Insights

• ❓ Vectors are defined by both magnitude and direction.
• 😥 The magnitude of a vector can be calculated as the distance between its initial and terminal points.
• ❓ The distance formula used to find the magnitude is derived from the Pythagorean theorem.
• ❎ The squared values in the formula ensure the length of a side is always positive.
• 💱 The change in x and y coordinates can be used to calculate the magnitude of a vector.
• 💱 The magnitude of a vector is the square root of the sum of the squared changes in x and y.
• 🔺 The Pythagorean theorem can be applied to find the length of the hypotenuse in the triangle representation of the vector.

## Transcript

• [Voiceover] We've already seen that a vector is defined by both its magnitude and its direction. What I want to do in this video is get some practice calculating or figuring out the magnitudes of vectors and I have a vector right over here, vector u, it is, it is, visually depicted here on our corded plane and I wanna figure out its magnitude and... Read More

### Q: How is the magnitude of a vector defined?

The magnitude of a vector is the length of the line connecting its initial and terminal points.

### Q: What is the distance formula used to calculate the magnitude of a vector?

The distance formula is derived from the Pythagorean theorem and is given by the square root of the sum of the squares of the changes in the x and y coordinates.

### Q: How do you calculate the change in y for a vector?

To calculate the change in y, subtract the y-coordinate of the initial point from the y-coordinate of the terminal point.

### Q: Why are the squared values important in the magnitude calculation?

The squared values ensure that the length of a side in the triangle representing the vector is always positive, regardless of the direction, as the square of a negative value is positive.

## Summary & Key Takeaways

• The video demonstrates how to find the magnitude of a vector by calculating the distance between its initial and terminal points.

• The magnitude of a vector can be determined using the distance formula, which is derived from the Pythagorean theorem.

• By analyzing the changes in the x and y coordinates, the video shows how to calculate the magnitude of a vector using the Pythagorean theorem.