Is My Vector Magnitude Calculation Correct?

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The discussion focuses on calculating the magnitude of the vector sum ||u+v|| given that ||u||=2, ||v||=√3, and u⋅v=1. The calculation involves using the equation ||u+v||² = ||u||² + 2(u⋅v) + ||v||², leading to ||u+v||² = 4 + 3 + 2 = 9. This results in ||u+v|| = 3, which is confirmed by multiple participants as correct. Additionally, there is a note about improving notation for clarity in future calculations. The final consensus is that the calculated magnitude of 3 is accurate.
Math9999

Homework Statement


If \parallel u\=2, \parallel v\=√3, and u*v=1, find \parallel u+v\.

Homework Equations


None.

The Attempt at a Solution


(u+v)(u+v)=(\parallel u\)2+2uv+(\parallel v\)2=4+3+2=9
\parallel u+v\\=3
So the answer I got is 3. Am I right? If not, then please correct me.
 
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Looks good to me.
 
Math9999 said:
If \parallel u\=2, \parallel v\=√3, and u*v=1, find \parallel u+v\.
Your notation is difficult to read. For magnitudes, which I think is what you're trying to convey here, just use the "pipe" character - |. On my keyboard it is above the backslash key, \.
 
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If ||u||=2, ||v||=√3, and u⋅v=1, find ||u+v||.

Here's my work:
||u+v||2=(u+v)(u+v)=||u||2+2uv+||v||2=4+3+2=9
||u+v||=3
So the answer I got is 3. Am I right? If not, then please correct me.
 
Still looks good to me.
 
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Thank you so much!
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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