1st order differential eqn raised to power of 1.7

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Homework Statement


This is the eqn I need to solve:
(dy/dx)^1.7 = c

Homework Equations





The Attempt at a Solution


1) 1.7ln(dy/dx) = c [since 'c' is an arbitrary constant, I'm writing ln(c) as 'c' itself]

2)ln(dy/dx) = c/1.7

3)dy/dx = e^(c/1.7)

4)y = xe^(c/1.7)

Now, the above solution says that y is a linear function of x. The solution is similar to what we obtain for "dy/dx = c", i.e. another linear solution. So I'm beginning to wonder whether what I did was correct. Can anyone help?
 
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You could just take the 1.7th root of the equation to get this

\frac{dy}{dx}=c^{\frac{1}{1.7}}

\frac{dy}{dx}=c'

Where c' is just another constant.

So in other words, it is just a linear function.
 
Thanks for the reply Prologue. So if this is a linear function too, then what exactly is the difference between the solution for "dy/dx = c" and "(dy/dx)^1.7 = c" besides the actual numerical value of dy/dx?
 
In differential equation terms...nothing. They have the same solution,

y = (arbitrary constant)x + (arbitrary constant)
 
Cool.. Thanks again...
 
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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