Evaluating Indefinite integrals

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The integral to evaluate is ∮ x² (1-x³)⁶ dx. The substitution u = 1 - x³ leads to du = -3x² dx, allowing for the transformation of the integral into -1/3 ∮ u⁶ du. The result simplifies to -1/21 (1-x³)⁷ + C, which raises questions about the correctness of the steps taken. The main concern is the circular integral symbol, which is not standard for indefinite integrals. Differentiating the final expression can confirm if the integration was performed correctly.
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Homework Statement


Evaluate

\oint x^2 (1-x^3)^6 dx

Homework Equations





The Attempt at a Solution



let u= 1-x^3
du= -3x^2
-1/3 du= x^2 dx
-1/3 \oint (u)^6
= -1/3 (u^7/7)
= -1/21 (1-x^3)^7 + C

Is this done correct? I think I followed all the right steps but there is something about it that has me wondering.
 
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the only problem I see is that circle on your integral symbol!

What do you get if you differentiate -(1/21)(1-x3)7+ C?
 
Yeah, the circle isn't supposed to be there I couldn't find a normal Integration sign.
 
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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