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anonymous
 one year ago
1.) Find a ⋅ b.
a = 7i  4j, b = 4i + 3j
<28, 12>
16
40
<11, 1>
2.)Let u = <4, 1>, v = <1, 6>. Find 2u + 4v.
<4, 22>
<4, 7>
<12, 26>
<10, 14>
anonymous
 one year ago
1.) Find a ⋅ b. a = 7i  4j, b = 4i + 3j <28, 12> 16 40 <11, 1> 2.)Let u = <4, 1>, v = <1, 6>. Find 2u + 4v. <4, 22> <4, 7> <12, 26> <10, 14>

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@princeharryyy a times b

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2the product @em2000

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2multiply i by i and j by j

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i got <11, 1> for the final answer, is that what you got? @princeharryyy

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2u added but we need to multiply

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2what happened @em2000

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.27*4 is 28 and 4*3 is 12

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@princeharryyy gotcha that makes sense. i got <12, 26> for #2 is that wrong?

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2but before i tell you about the first and second answer, are you doing scalar vectors.

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2then it's my bad. the first ones answer won't be A part

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@princeharryyy actually im not sure, the instructions dont specify

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2< and > means vectors that's why i asked

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2let me tell how they work

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2i.i =1, j.j =1 i.j =0 (iand j are at 90 degrees)

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2dw:1435096143456:dw

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2i, j, k are all at 90 degrees any two quantities when multiplied at 90 degrees gives 0 as i.j.cos90 =0, j.k.cos90 =0, k.i.cos90 =0

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2are you getting it @em2000

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2So, for the first question a = 7i  4j, b = 4i + 3j a.b is written as a.b = (7i  4j).(4i  3j)

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2so, a.b = 7*4*i.i 7*3*i.j 4*4*j.j4*3j.j so, a.b = 280012 =16 answer @em2000

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2for the first question

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2now for the second

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2Let u = <4, 1>, v = <1, 6>. Find 2u + 4v. => u = 4i+1j, v = 1i+6j 2u+4v = 2(4i+1j) +4(1i+6j) = 8i2j 4i+24j = 4i+22j => <4,22> answer @em2000

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2which is option A @em2000 . Did you get it.

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.0Scalar multiplication of vectors: \(\bf{A} = \sf A_x + B_y\) \(\bf B = \sf B_x + B_y\) \(\bf A \cdot B \sf = A_xB_x + A_yB_y\) Answer is scalar.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@princeharryyy thank u so much

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2Do you know the answers now @em2000

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2for first one it is 16 and for second one i t is <4,22> @em2000

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.0\(\bf A \cdot B \sf = A_xB_x + A_yB_y = (7)(4) + (4)(3) = 28  12 = 16\)

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.0dw:1435096919904:dw

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2thanks @mathstudent55. Sorry, for the medal she patiently tried to understand the concept. That's why I gave her the medal. Sorry, that I can't offer them to two people on one question. @em2000 could you please give a medal to @mathstudent55

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2@mathstudent55 tried to help you out as well.

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2no not to me @em2000 , but to @mathstudent55

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.0@princeharryyy Don't worry about the medal. I gave you one because I thought your explanation was great, and you deserved it!

princeharryyy
 one year ago
Best ResponseYou've already chosen the best response.2I never worry about medals @mathstudent55 but most people at open study help others for medals.
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