Integrating x^2e^-3lnx: Tips and Tricks for Solving Tricky Integrals

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To solve the integral of x^2e^-3lnx, it is essential to simplify e^-3lnx using properties of logarithms and exponentials. This can be rewritten as e^(ln(x^-3)), which simplifies to x^-3. Thus, the integral transforms to int(x^2 * x^-3), leading to int(x^-1). The final integral simplifies to ln|x| + C, where C is the constant of integration. Understanding the relationship between logarithmic and exponential functions is crucial for tackling similar integrals.
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Homework Statement


int((x^2)(e^-3lnx))

anyone tips for this?

Homework Equations


The Attempt at a Solution

 
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Hint:

<br /> e^{-3 \, \ln{(x)}} = e^{\ln{(x^{-3})}} = ?<br />
 
Dickfore said:
Hint:

<br /> e^{-3 \, \ln{(x)}} = e^{\ln{(x^{-3})}} = ?<br />

now I get int (x^2)(e^(1/x^3)) then? stuck here
 
You are wrong. What does e^{\ln{y}} equal to? Use the property that the (natural) logarithm is the inverse function of the (natural) exponential function.
 
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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