Solving a problem regarding Existence theorem.

bravoman
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Homework Statement


Given the equation dy/dx = y^4 - x^4, y(0) = 7, determine whether the existence/uniqueness theorem implies that the given initial value problem has a unique solution.

Homework Equations


Existence/Uniqueness Theorem

The Attempt at a Solution


To my understanding, you must assign f(x,y) = y^4 - x^4 then derive f(x,y) in terms of y.

f'(x,y) = 4y^3

This is as far as I have gotten.
 
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bravoman said:

Homework Statement


Given the equation dy/dx = y^4 - x^4, y(0) = 7, determine whether the existence/uniqueness theorem implies that the given initial value problem has a unique solution.

Homework Equations


Existence/Uniqueness Theorem

The Attempt at a Solution


To my understanding, you must assign f(x,y) = y^4 - x^4 then derive f(x,y) in terms of y.

f'(x,y) = 4y^3

This is as far as I have gotten.

What is the statement of the existence/uniqueness theorem? How does it apply in your case?
 
I need to use the theorem to determine of the equation dy/dx = y^4 - x^4 has a unique solution at point (0,7). Is that correct?
 
Ray Vickson said:
What is the statement of the existence/uniqueness theorem? How does it apply in your case?

bravoman said:
I need to use the theorem to determine of the equation dy/dx = y^4 - x^4 has a unique solution at point (0,7). Is that correct?
That isn't what Ray asked. What does the Existence and Uniqueness Theorem say?
 
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