Characteristic Lines for 2D Equations with a Boundary Condition

andrey21
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Find the characteristic lines for the equation:

2 du/dx + 8x du/dt = 16x




Here's my attempt

a = 2 b = 8x c = 16x

Using dt/dx = b/a = 8x/2 = 4x

t = 2x2 + C

C = t1 -2x12

Hence the characteristic is:

t = 2x2 + t1 - 2x12
 
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Please any reply would be great, am I correct with my answer??
 
1. You can't expect people to anwer within two hours. People don't just sit around waiting for a new post!

2. You can get yourself an infraction and even banned for "bumping" threads just to get them moved to the top of the list again.

3. I don't even understand your answer. The characteristic is a relation between x and y. There is no "y" in your answer but there is a "t" which shouldn't be there.
 
All of the examples I have been given they do not contain a "y", I should have stated the boundary condition is u(x,0) = x^(2).
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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