Integral of sin(lnx) + (lnx)^3/2 w.r.t. x

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The discussion focuses on finding the derivative of the integral g(x) = integral from 0 to lnx of (sin(t) + t^(3/2)) dt. The derivative d/dx g(x) is computed using the chain rule, resulting in the expression sin(lnx)(1/x) + (lnx)^(3/2)(1/x). Participants emphasize the importance of the fundamental theorem of calculus, particularly its second part, in solving such problems. They suggest reviewing relevant examples in the textbook for clarity on the derivative of an integral. The conversation highlights the application of calculus principles in evaluating integrals and their derivatives.
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g(x) = integral 0 to lnx (sin(t)+t^3/2))dt

find d/dx g(x):

let u = lnx


= sin(u) + u^3/2 du/dx
= sin(lnx)(1/x) + x^3/2(1/x)

Thanks
 
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What is your question?
 
I believe what you need to examine is the fundamental theorem of calculus, part 2. Check your text.

edit: in that section, you'll probably see some examples where they find the derivative of the integral of some function...
 
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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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