Trying to find two vectors with known sum, what am I doing wrong?

Thread starter Joshua G
Start date Sep 6, 2019
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Sum Vectors

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The discussion revolves around finding two vectors, v_1 and v_2, with a known sum. The vectors provided are v_1 = <-8/21,-20/21> and v_2 = <50/21,-20/21>. A participant notes that the dot product of v_2 and <2,5> equals zero, indicating they are perpendicular. However, another participant points out an arithmetic error in the calculations related to the equation 5k + b = 0. The conversation emphasizes the importance of clearly typing out work instead of using images for better clarity.

Sep 6, 2019

Joshua G

Homework Statement: I'm trying to find two vectors whose sum is <2,0> ; where v_1 is parallel to <2,5> and v_2 is perpendicular to <2,5>.

Relevant Equations: <v1>*<v2>=0 for orthogonal
<v1>*<v2>=1 for parallel

v_1 = <-8/21,-20/21>
v_2 = <50/21,-20/21> When I take the dot product of v_2 and <2,5> I get zero, indicating they are perpendicular. Sorry for the hand writing.

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Sep 6, 2019

Orodruin

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Your arithmetic is off. From 5k + b = 0 you seem to have concluded that b = 5k.

In the future, please type out your work rather than attaching images.

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