How Do You Integrate the Square of dx/dt?

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Homework Help Overview

The discussion revolves around the integration of the square of the derivative of a variable with respect to time, specifically the expression \(\int\left(\frac{dx}{dt}\right)^{2}dt\). Participants are exploring the implications of this integral in the context of calculus and differential equations.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants suggest rewriting the integral in different forms to clarify the relationship between the variables. There is a focus on understanding how to handle the dependence of \(x\) on \(t\) and the implications of this dependence on the integration process.

Discussion Status

The discussion is ongoing, with participants providing alternative representations of the integral and questioning the ability to eliminate time dependence. There is recognition that the solution may vary based on the specific function \(x(t)\) being considered.

Contextual Notes

Some participants note that the integration's outcome is contingent on the functional form of \(x(t)\), indicating that different functions will lead to different complexities in integration.

raisin_raisin
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Hey, not really homework but I am just having a total mind blank and would be grateful if someone could help me.
\int\left(\frac{dx}{dt}\right)^{2}dt=?
I even have the answer my brain is just refusing to play along though and I just can't picture how to work it out properly at the moment.
Thanks!
 
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try writing it as

\int \frac{dx}{dt} \frac{dx}{dt} dtinstead.
 
rock.freak667 said:
try writing it as

\int \frac{dx}{dt} \frac{dx}{dt} dt


instead.
Thanks for your reply.
In that case I don't have brain freeze I just don't know. I just want to cancel the dt's but then
I get
\int \frac{dx}{dt}dx
which I don't know how to handle.
 
It's not the sort of an expression where you can eliminate the t dependence. The answer depends on how x depends on t. E.g. if x(t)=t^2, then it's an easy elementary integral, if x(t)=e^(t^2), it's not an elementary integral.
 

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