Exam 39:Vectors and Dot Products

arrow
  • Select Tags
search iconSearch Question
  • Select Tags

Given vectors u=u1,u2\mathbf { u } = \left\langle u _ { 1 } , u _ { 2 } \right\rangle , v=v1,v2\mathbf { v } = \left\langle v _ { 1 } , v _ { 2 } \right\rangle and w=w1,w2\mathbf { w } = \left\langle w _ { 1 } , w _ { 2 } \right\rangle determine whether the result of the following expression is a vector or a scalar. 6w3w6 w \cdot 3 w

Free
(Multiple Choice)
4.9/5
(35)
Correct Answer:
Verified

B

Find the angle between the vectors u and v.​ u=cos(π3)i+sin(π3)j\mathbf { u } = \cos \left( \frac { \pi } { 3 } \right) \mathbf { i } + \sin \left( \frac { \pi } { 3 } \right) \mathbf { j } , v=cos(5π4)i+sin(5π4)j\mathbf { v } = \cos \left( \frac { 5 \pi } { 4 } \right) \mathbf { i } + \sin \left( \frac { 5 \pi } { 4 } \right) \mathbf { j }

Free
(Multiple Choice)
4.8/5
(34)
Correct Answer:
Verified

D

Determine the work done by a crane lifting a 2,800-pound car 7 feet.

Free
(Multiple Choice)
4.8/5
(33)
Correct Answer:
Verified

A

Use the vector u=3,2\mathbf { u } = \langle 3,2 \rangle to find the indicated quantity.State whether the result is a vector or a scalar.​ u.u\mathbf { u } ^\mathbf{.}\mathbf { u } ^ { }

(Multiple Choice)
4.9/5
(28)

​Find the projection of u onto v if , u=5,4\mathbf { u } = \langle - 5 , - 4 \rangle , v=2,5\mathbf { v } = \langle 2 , - 5 \rangle .

(Multiple Choice)
4.8/5
(34)

The vector u=3900,4000\mathbf { u } = \langle 3900,4000 \rangle gives the number of units of two models of laptops produced by a company.The vector u=1450,1000\mathbf { u } = \langle 1450,1000 \rangle gives the prices (in dollars)of the two models of laptops,respectively.Identify the vector operation used to increase revenue by 6%.

(Multiple Choice)
4.9/5
(42)

Use vectors to find the measure of the angle at vertex B of triangle ABC,when A=(5,1)A = ( 5,1 ) , B=(5,1)B = ( - 5,1 ) ,and C=(3,5)C = ( - 3 , - 5 ) .Round answer to two decimal places.

(Multiple Choice)
4.8/5
(28)

Given u=3,2\mathbf { u } = \langle 3 , - 2 \rangle and v=1,3\mathbf { v } = \langle 1 , - 3 \rangle ,find uvu\cdot v .

(Multiple Choice)
4.7/5
(37)

Use the dot product to find the magnitude of u if u=3i+6j\mathbf { u } = - 3 \mathbf { i } + 6 \mathbf { j }

(Multiple Choice)
4.8/5
(38)

Determine whether u are v and orthogonal,parallel,or neither. u=43,32,v=16,18\mathbf { u } = \left\langle \frac { - 4 } { 3 } , \frac { 3 } { 2 } \right\rangle , \mathbf { v } = \langle 16 , - 18 \rangle

(Multiple Choice)
4.8/5
(39)

Determine u.vu^.v if u=5,v=6\| \mathbf { u } \| = 5 , \| \mathbf { v } \| = 6 ,and θ=π3\theta = \frac { \pi } { 3 } where θ is the angle between u and v.Round answer to two decimal places.

(Multiple Choice)
4.7/5
(32)

Determine whether u are v and orthogonal,parallel,or neither. u=13,52\mathbf { u } = \left\langle \frac { 1 } { 3 } , \frac { 5 } { 2 } \right\rangle , v=4,30\mathbf { v } = \langle - 4 , - 30 \rangle

(Multiple Choice)
4.9/5
(34)

A force of 45 pounds is exerted along a rope attached to a crate at an angle of 30° above the horizontal.The crate is moved 31 feet horizontally.How much work has been accomplished? Round your answer to one decimal place.

(Multiple Choice)
4.8/5
(33)

Find the angle θ between the vectors.​ =\langle6,2\rangle =\langle7,0\rangle ​ (Round the answer to 2 decimal places. ) ​

(Multiple Choice)
4.9/5
(33)

Find the projection of u onto v.​ =\langle-5,-5\rangle =\langle-5,-1\rangle ​

(Multiple Choice)
4.9/5
(42)

Find the projection of u onto v.Then write u as the sum of two orthogonal vectors,one of which is projvu\operatorname { proj } _ { \mathrm { v } } \mathbf { u } .​ ​​ u=30,5\mathbf { u } = \langle 30,5 \rangle v=1,6\mathbf { v } = \langle 1 , - 6 \rangle

(Multiple Choice)
4.8/5
(35)

Find the projection of u onto v.​ =\langle0,4\rangle =\langle3,20\rangle ​

(Multiple Choice)
4.8/5
(38)

Find the angle between the vectors u and v if u=3i2j\mathbf { u } = 3 \mathbf { i } - 2 \mathbf { j } and u=3i+2j\mathbf { u } = 3 \mathbf { i } + 2 \mathbf { j } Round your answer to two decimal places.

(Multiple Choice)
4.9/5
(32)

Use the vectors u=2,4\mathbf { u } = \langle 2,4 \rangle , v=5,3\mathbf { v } = \langle - 5,3 \rangle and w=3,1\mathbf { w } = \langle 3 , - 1 \rangle to find the indicated quantity.State whether the result is a vector or a scalar.​ (v.u)(w.v)\left( \mathbf { v } ^ { . } \mathbf { u } \right) - \left( \mathbf { w } ^ { . } \mathbf { v } \right)

(Multiple Choice)
4.8/5
(38)

Given vectors u=1,3\mathbf { u } = \langle - 1,3 \rangle and v=1,4\mathbf { v } = \langle 1,4 \rangle determine the quantity indicated below. 2u4v- 2 \mathbf { u }{ \cdot}- 4 \mathbf { v }

(Multiple Choice)
4.9/5
(25)
Showing 1 - 20 of 67
close modal

Filters

  • Essay(0)
  • Multiple Choice(0)
  • Short Answer(0)
  • True False(0)
  • Matching(0)