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Copyright © 2011 Pearson, Inc.

Copyright © 2011 Pearson, Inc.. 6.1 Day 1 Vectors in the Plane Goal: Apply the arithmetic of vectors

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Copyright © 2011 Pearson, Inc.

Copyright © 2011 Pearson, Inc.

6.1 Day 1

Vectors in the Plane

Goal: Apply the arithmetic of vectors.

Copyright © 2011 Pearson, Inc. Slide 6.1 - 3

What you’ll learn about

Two-Dimensional Vectors Vector Operations Direction Angles Applications of Vectors

… and whyThese topics are important in many real-world applications, such as calculating the effect of the wind on an airplane’s path.

Copyright © 2011 Pearson, Inc.

One vs. Two Quantities

Magnitude (Size) temperature distance Speed mass

Magnitude & Direction force velocity weight

Slide 6.1 - 4

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Vector -

magnitude:

direction:

Slide 6.1 - 5

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Vocabulary

Component Form:

Components:

Standard representation:

Zero vector:

Slide 6.1 - 6

Copyright © 2011 Pearson, Inc. Slide 6.1 - 7

Initial Point, Terminal Point, Equivalent

Copyright © 2011 Pearson, Inc. Slide 6.1 - 8

Head Minus Tail (HMT) Rule

If an arrow has initial point x1, y

1 and terminal point

x2, y

2 , it represents the vector x2 x

1, y

2 y

1.

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Example 1: Showing Vectors are Equivalent

Show that the arrow from R = (-4, 2) to S = (-1, 6) is equivalent to the arrow from P = (2, -1) to Q = (5, 3).

Slide 6.1 - 9

Copyright © 2011 Pearson, Inc. Slide 6.1 - 10

Magnitude

If v is represented by the arrow from x1, y

1 to x2, y

2 ,then

v x2 x

1 2 y

2 y

1 2.

If v a,b , then v a2 b2 .

Copyright © 2011 Pearson, Inc. Slide 6.1 - 11

Example 2: Finding Magnitude of a Vector

Find the magnitude of v represented by PQ,

where P (3, 4) and Q (5,2).

Copyright © 2011 Pearson, Inc. Slide 6.1 - 12

Vector Addition

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Vector Addition

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Example 3: Performing Vector Addition

Let u = and v = . Find u + v.

Slide 6.1 - 14

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Parallelogram Representation

Slide 6.1 - 15

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Scalar Multiplication

scalar:

Slide 6.1 - 16

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Example 3: Performing Vector Operations

Let u = and v = . Find 2u.

2u - v

Slide 6.1 - 17

Copyright © 2011 Pearson, Inc. Slide 6.1 - 18

Exit Ticket Performing Vector Operations

Let u 2, 1 and v 5,3 . Find 3u v.

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6.1 Day 2

Vectors in the Plane

Goal: Use vectors to solve real-world problems.

Copyright © 2011 Pearson, Inc. Slide 6.1 - 20

Resolving the Vector-

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Example 5a: Finding the Components of a Vector

Find the components of the vector v with direction angle 115˚ and magnitude 6.

Slide 6.1 - 21

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Example 5b: Finding the Components of a Vector

Find the exact components of the vector v with direction

angle 30˚ and magnitude 8.

Slide 6.1 - 22

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Example 5c: Finding the Components of a Vector

Draw the indicated vector and show the components into which it is resolved.

A cannonball is launched with a speed of 170 m/s at 40° above the horizontal.

Slide 6.1 - 23

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Velocity and Speed

The velocity of a moving object is a vector

because velocity has both magnitude and

direction. The magnitude of velocity is ________.

________________ - the angle that a line of travel makes with due north, measured clockwise

Slide 6.1 - 24

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Example 7: Writing Velocity as a Vector

A DC-10 jet aircraft is flying on a bearing of 65˚ at 500 mph. Find the component form of the velocity of the airplane. Recall that the bearing is the angle that the line of travel makes with due north, measured clockwise.

Slide 6.1 - 25

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Calculate Magnitude and Direction.

Calculate the magnitude and direction of the vector.

Slide 6.1 - 26

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Example: Find the magnitude and direction angle of each vector.

a) b)

Slide 6.1 - 27

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Summary

Magnitude and direction

magnitude and direction

Slide 6.1 - 28

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6.1 Day 3

Vectors in the Plane

Goal: Calculate the resultant vector.

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Resultant Vector

Slide 6.1 - 30

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Example: Add the Vectors to find the Resultant Vector

Slide 6.1 - 31

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Example: Calculating the Effect of Wind Velocity

A jet carrying Dora the Explorer is flying at 400 mph on a course with a bearing of 30º. If the jet experiences a crosswind blowing due south at 20 mph, find the resultant speed and direction of the jet. Round all values throughout the problem and the final answer to the nearest tenth.

Slide 6.1 - 32

Copyright © 2011 Pearson, Inc. Slide 6.1 - 33

: Combining Forces

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Solution

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