Solve 1st Order ODE Homework - Get Help Now

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SUMMARY

The discussion focuses on solving a first-order ordinary differential equation (ODE) and clarifies the misconception regarding the integral of the term involving ln(y). The correct approach involves recognizing that the integral of dy/y equals ln(y) + C, which is not applicable in the given equation. The standard method for solving second-order linear homogeneous differential equations is to assume a solution of the form y_k = e^(k*x), where k is a complex number. The solution can be expressed as a linear combination of the exponential functions y = C_1e^(k_1*x) + C_2e^(k_2*x).

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  • Knowledge of exponential functions and their properties
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Homework Statement


Solve the below differential equation


Homework Equations





The Attempt at a Solution


I have attached my attempt at solution. But I don't how to get rid of (ln y) term in my equation i.e, i Don't know how to write in terms of y. Please help
 

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It is not true that \int \frac{d^2 y}{y} = \ln y + C. What is true is that \int \frac{dy}{y} = \ln y + C. Since we do not have the form \frac{dy}{y} anywhere in our equation, we cannot apply that integral to this equation.
The standard method with which we solve this type of differential equation (second order linear homogeneous) is to assume the solution is a linear combination of exponential functions of the form yk = ekx where k may be a complex number, and substitute this assumption into the equation in order to solve for the various possible values of k.
That is, if you find y_1 = e^{k_1x} and y_2 = e^{k_2x} both satisfy the differential equation, then y = C_1e^{k_1x} + C_2e^{k_2x} also satisfies the original equation for any particular pair of values C_1 and C_2.
However, another plausible method is that you may already know two functions whose second derivative yields the negation of the original function. It then stands to reason that any linear combination of those two functions solves this equation.
 

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