What is the magnitude of the sum of the following vectors?

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SUMMARY

The magnitude of the sum of the vectors A = i + 5j - k, B = 4i - j - 5k, and C = -i + j is calculated by first summing the components. The correct component addition yields 4i + 6j - 6k. The magnitude is then computed using the formula √(x² + y² + z²), resulting in √(4² + 6² + (-6)²) = √(16 + 36 + 36) = √88, which simplifies to approximately 9.38. The initial calculation error stemmed from incorrect component addition.

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Mdhiggenz
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Homework Statement



What is the magnitude of the sum of the following vectors?

A= i +5j -k

B= 4i-j-5k

C= -i+j


Homework Equations






The Attempt at a Solution



What I did was I added i+4i-i to get 5i, I also added 5k+j-5 to get 5j, likewise for k to get -6k

and did the squareroot of (25+25+36) to get squareroot of 86 or 9.27 however that is not the right answer. What am I doing wrong?

Thank you
 
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Mdhiggenz said:
What I did was I added i+4i-i to get 5i,
Redo that addition.
 

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