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Find y as a function of x if y′′′−9y′′+20y′=48eˣy(0)=26,v′(0)=28,y′′(0)=15.

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Final answer:

To solve the given differential equation y′′′−9y′′+20y′=48eˣ, we can use the method of undetermined coefficients. Assuming y = Aeˣ, we find that A = 4, so the solution to the equation is y = 4eˣ.

Step-by-step explanation:

To find y as a function of x, we need to solve the given differential equation y′′′−9y′′+20y′=48eˣ for y. We can use the method of undetermined coefficients to solve this equation. Let's assume that y = Aeˣ, where A is a constant. Now, we'll take the derivatives of y and substitute them into the differential equation to find the value of A.

Substituting y = Aeˣ, y' = Aeˣ, y'' = Aeˣ, and y''' = Aeˣ into the differential equation, we get:

Aeˣ - 9Aeˣ + 20Aeˣ = 48eˣ

Combine like terms:

12Aeˣ = 48eˣ

Cancelling the exponential terms, we get 12A = 48. Solving for A, we find A = 4.

Therefore, y = 4eˣ is the solution to the differential equation.

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