Verifying Vector Equations: Proving Properties of Cross Products

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The discussion focuses on proving two properties of cross products: p x (q + r) = p x q + p x r and p x (q x r) = (p x q) x r. The user is attempting to verify the first property by expanding the left-hand side using the components of vectors p, q, and r. A response confirms that the user is on the right track but emphasizes that further steps are needed to complete the cross product calculation. The conversation highlights the importance of thorough mathematical proof in vector algebra.
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2 questions i have;
if true

1. proove that; p x ( q + r ) = p x q + p x r

2. and p x ( q x r ) = ( p x q ) x r

where;

p = p1i + p2j + p3k
q = q1i + q2j + q3k
r = r1i + r2j + r3k

i have left handside p x (q + r) = (p1i + p2j + p3k)( (q1+ r1)i + (q2+ r2)j + (q3+ r3)k)

am i on the right track?
 
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You're on the right track. But you've barely started. Now do the cross product.
 
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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