Download the App!

Get 24/7 study help with the Numerade app for iOS and Android! Enter your email for an invite.

Sent to:
Search glass icon
  • Login
  • Textbooks
  • Ask our Educators
  • Study Tools
    Study Groups Bootcamps Quizzes AI Tutor iOS Student App Android Student App StudyParty
  • For Educators
    Become an educator Educator app for iPad Our educators
  • For Schools

Problem

If $ u $ is a unit vector, find $ u \cdot v $ and…

01:50

Question

Answered step-by-step

Problem 10 Easy Difficulty

Find $ a \cdot b $.

$ \mid a \mid = 80 $ , $ \mid b \mid = 50 $ , the angle between $ a $ and $ b $ is $ \frac{3 \pi}{4} $


Video Answer

Solved by verified expert

preview
Numerade Logo

This problem has been solved!

Try Numerade free for 7 days

Bobby Barnes
University of North Texas

Like

Report

Textbook Answer

Official textbook answer

Video by Bobby Barnes

Numerade Educator

This textbook answer is only visible when subscribed! Please subscribe to view the answer

More Answers

01:33

Chris Trentman

Related Courses

Calculus 3

Calculus: Early Transcendentals

Chapter 12

Vectors and the Geometry of Space

Section 3

The Dot Product

Related Topics

Vectors

Discussion

You must be signed in to discuss.
Top Calculus 3 Educators
Anna Marie Vagnozzi

Campbell University

Heather Zimmers

Oregon State University

Kayleah Tsai

Harvey Mudd College

Kristen Karbon

University of Michigan - Ann Arbor

Calculus 3 Courses

Lectures

Video Thumbnail

02:56

Vectors Intro

In mathematics, a vector (from the Latin word "vehere" meaning "to carry") is a geometric entity that has magnitude (or length) and direction. Vectors can be added to other vectors according to vector algebra. Vectors play an important role in physics, engineering, and mathematics.

Video Thumbnail

11:08

Vector Basics Overview

In mathematics, a vector (from the Latin word "vehere" which means "to carry") is a geometric object that has a magnitude (or length) and direction. A vector can be thought of as an arrow in Euclidean space, drawn from the origin of the space to a point, and denoted by a letter. The magnitude of the vector is the distance from the origin to the point, and the direction is the angle between the direction of the vector and the axis, measured counterclockwise.

Join Course
Recommended Videos

00:23

Find $ a \cdot b $.

<…

01:02

Find $a \cdot b$
$|\mat…

01:28

The angle between $\vec{A}…

01:15

If $|\vec{a} \cdot \vec{b}…

01:18

Given that $\vec{A}+\vec{B…

02:01

Given the side $a=1$ and a…

02:09

Given the sides $a=3, b=4$…

01:42

Given, $\mathbf{P}=\mathbf…

04:18

$\mathrm{C}^{\rightarrow}=…

01:18

If $|\vec{A}+\vec{B}|=|\ve…

01:19

If $|\vec{A}+\vec{B}|=|\ve…

02:56

If $\vec{a}+\vec{b}+\vec{c…

02:02

Given $\mathbf{R}=\mathbf{…

01:57

If $|\vec{A}+\vec{B}|=|\ve…

Watch More Solved Questions in Chapter 12

Problem 1
Problem 2
Problem 3
Problem 4
Problem 5
Problem 6
Problem 7
Problem 8
Problem 9
Problem 10
Problem 11
Problem 12
Problem 13
Problem 14
Problem 15
Problem 16
Problem 17
Problem 18
Problem 19
Problem 20
Problem 21
Problem 22
Problem 23
Problem 24
Problem 25
Problem 26
Problem 27
Problem 28
Problem 29
Problem 30
Problem 31
Problem 32
Problem 33
Problem 34
Problem 35
Problem 36
Problem 37
Problem 38
Problem 39
Problem 40
Problem 41
Problem 42
Problem 43
Problem 44
Problem 45
Problem 46
Problem 47
Problem 48
Problem 49
Problem 50
Problem 51
Problem 52
Problem 53
Problem 54
Problem 55
Problem 56
Problem 57
Problem 58
Problem 59
Problem 60
Problem 61
Problem 62
Problem 63
Problem 64
Problem 65

Video Transcript

So this case for us to find the dot product, the form what are going to want to use is the one that I have on the board where it is going to be the dot product of A and B is the magnitudes of each of those multiplied together times the cosine of the angle between them. And we have all that already because they just give it to us. So we just need to come over here and plug all that in now. So we know that the magnitude of a is 80. The magnitude of the is 50. And then, you know, the angle between them is three pi fourth. So now we just multiply everything together. Uh, so 80? Yeah. Times 40 would be armed up 40 80 times. 50 should be 4000. Co sign of three pi force. Well, that is where co sign is negative. It would be negative. Route two or two and then simplifying the two in the 4000 would give us 2000, so this would be negative 2000 route to. So this is going to be our product

Get More Help with this Textbook
James Stewart

Calculus: Early Transcendentals

View More Answers From This Book

Find Another Textbook

Study Groups
Study with other students and unlock Numerade solutions for free.
Math (Geometry, Algebra I and II) with Nancy
Arrow icon
Participants icon
65
Hosted by: Ay?Enur Çal???R
Math (Algebra 2 & AP Calculus AB) with Yovanny
Arrow icon
Participants icon
43
Hosted by: Alonso M
See More

Related Topics

Vectors

Top Calculus 3 Educators
Anna Marie Vagnozzi

Campbell University

Heather Zimmers

Oregon State University

Kayleah Tsai

Harvey Mudd College

Kristen Karbon

University of Michigan - Ann Arbor

Calculus 3 Courses

Lectures

Video Thumbnail

02:56

Vectors Intro

In mathematics, a vector (from the Latin word "vehere" meaning "to carry") is a geometric entity that has magnitude (or length) and direction. Vectors can be added to other vectors according to vector algebra. Vectors play an important role in physics, engineering, and mathematics.

Video Thumbnail

11:08

Vector Basics Overview

In mathematics, a vector (from the Latin word "vehere" which means "to carry") is a geometric object that has a magnitude (or length) and direction. A vector can be thought of as an arrow in Euclidean space, drawn from the origin of the space to a point, and denoted by a letter. The magnitude of the vector is the distance from the origin to the point, and the direction is the angle between the direction of the vector and the axis, measured counterclockwise.

Join Course
Recommended Videos

00:23

Find $ a \cdot b $. $ \mid a \mid = 7 $ , $ \mid b \mid = 4 $ , the angle be…

01:02

Find $a \cdot b$ $|\mathbf{a}|=6, \quad|\mathbf{b}|=5,$ the angle between $\mat…

01:28

The angle between $\vec{A}+\vec{B}$ and $\vec{A} \times \vec{B}$ is a. 0 b. $\p…

01:15

If $|\vec{a} \cdot \vec{b}|-\sqrt{3}|\vec{a} \times \vec{b}|$, then the angle b…

01:18

Given that $\vec{A}+\vec{B}=\vec{C} .$ If $|\vec{A}|=4,|\vec{B}|=5$ and $|\vec{…

02:01

Given the side $a=1$ and angles $A=\pi / 4$ and $B=\pi / 3$ of a triangle $\mat…

02:09

Given the sides $a=3, b=4$, and included angle $\mathrm{C}=\pi / 4$ of triangle…

01:42

Given, $\mathbf{P}=\mathbf{A}+\mathbf{B}$ and $P=A+B .$ The angle between $\mat…

04:18

$\mathrm{C}^{\rightarrow}=\mathrm{A}^{\rightarrow}+\mathrm{B}^{\rightarrow}$ an…

01:18

If $|\vec{A}+\vec{B}|=|\vec{A}|=|\vec{B}|$, then the angle between $\vec{A}$ an…

01:19

If $|\vec{A}+\vec{B}|=|\vec{A}|=|\vec{B}|$, then the angle between $\vec{A}$ an…

02:56

If $\vec{a}+\vec{b}+\vec{c}-0,|\vec{a}|-3,|\vec{b}|-5,|\vec{c}|-7$, then angle …

02:02

Given $\mathbf{R}=\mathbf{A}+\mathbf{B}$ and $R=A=B .$ The angle between $\math…

01:57

If $|\vec{A}+\vec{B}|=|\vec{A}-\vec{B}|$, then the angle between $A$ and $\bar{…
Additional Mathematics Questions

02:30

'Convert 2.015 bar on 15 in p by q form full solution the answer will g…

02:11

'PQRS is a parallelogram, x = _______________________
ST=x + 8
TQ…

00:57

'SOMEONE HELP ASAP!!!!!!'

02:58

'A point Q is shown on the number line . If we move 7 units to the righ…

00:59

'Its meaningful picture
DoC ToRS
IMDIA
COV1019
STUPID PeOpL…

01:47

'Please help me solve this.
log6 (n _ 3) + log6 (| 2) = logs (3)…

01:23

'help fast please!!!!!!!!!!!!!!!!!!!!!!!!!!!!'

01:36

"Mrs. Susheela have a square plot with the measurements as shown in the…

03:20

'pls solve it correctly plz
Simplify > ()x7- # {x; ();xj-xi+ix&#x…

05:51

'Plz tell me fast this ans I will mark as brainlist. '

Add To Playlist

Hmmm, doesn't seem like you have any playlists. Please add your first playlist.

Create a New Playlist

`

Share Question

Copy Link

OR

Enter Friends' Emails

Report Question

Get 24/7 study help with our app

 

Available on iOS and Android

About
  • Our Story
  • Careers
  • Our Educators
  • Numerade Blog
Browse
  • Bootcamps
  • Books
  • Topics
  • Test Prep
  • Ask Directory
  • Online Tutors
  • Tutors Near Me
Support
  • Help
  • Privacy Policy
  • Terms of Service
Get started