Missing Power Solving the PDE (Solution included)

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The discussion revolves around solving a partial differential equation (PDE) with a specific initial condition. The user presents their attempt at the solution, which involves integrating the expression xt = 18s² + 3sT to find u(s,t). However, they express confusion regarding the missing power of (3/2)sT in their final equation for u(s,t). Participants emphasize the importance of clearly stating the problem and initial conditions when seeking help. The main focus is on clarifying the integration process and ensuring all terms are accounted for in the solution.
zr95
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Homework Statement


upload_2016-5-1_18-56-40.png


Homework Equations

The Attempt at a Solution


integral[du]= Integral[xt ds]
xt=18s2+3sT
so,
u=Integral[18s2+3sT]
u=6s3+(3/2)s2T+C
C=eT2

This is what I did and the solution is below. I'm unsure where the missing power on the (3/2)sT went in the u(s,t) equation.[/B]
upload_2016-5-1_19-4-41.png
 
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zr95 said:

Homework Statement


View attachment 100094

Homework Equations



The Attempt at a Solution


integral[du]= Integral[xt ds]
xt=18s2+3sT
so,
u=Integral[18s2+3sT]
u=6s3+(3/2)s2T+C
C=eT2

This is what I did and the solution is below. I'm unsure where the missing power on the (3/2)sT went in the u(s,t) equation.
View attachment 100096
Let's make the initial image somewhat readable:
upload_2016-5-2_9-28-36.png


You reaaly need to give a complete statement of your problem in the body of your initial post. Here, are we to assume that you are asked to solve that PDE with the stated initial condition?
 
The goal is to solve the cauchy pde.
 
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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