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Consider the following IVP, y ′ =e 9y−x ,y(0)=0

(a) Use substitution to solve.
(b) Use another method to solve.
(c) Determine the interval of validity.

User Ex
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1 Answer

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Final answer:

To solve the given IVP using substitution, we can let u = e^9y and differentiate to substitute back into the original equation. Alternatively, we can use the integrating factor method by multiplying both sides by e^(9x) and integrating. The solution for y in terms of x can be obtained from this equation.

Step-by-step explanation:

To solve the IVP y' = e^9y - x, y(0) = 0, we can use substitution. First, we can make a substitution by letting u = e^9y. Then, differentiate both sides of the equation to get du = 9e^9y dy. Substituting these back into the original equation, we get du = 9u - x dx.

To solve this differential equation, we can use the integrating factor method. Multiply both sides of the equation by e^(9x) to get e^(9x) du = 9u e^(9x) - x e^(9x) dx. Now, we can integrate both sides to get e^(9x) u = ∫(9u e^(9x) - x e^(9x)) dx. Solving this integral and rearranging the equation, we get the solution for y in terms of x.

User Jcuenod
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