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Solve the following differential equation for its general solution. It is given that two linearly independent solutions are e−3x and xe−3x. (Do not use decimal fractions anywhere.) fy(4)+(6f+m)y(3)+(9f+l+6m)y′′+(9m+6l)y′+9ly=0 Where, f,m, and l are the number of letters in your first name, middle name, and last name respectively.

User Cruiser
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Final Answer:

The general solution to the given differential equation is
\(y(x) = c_1 e^(-3x) + c_2 x e^(-3x)\), where
\(c_1\) and \(c_2\) are arbitrary constants.

Step-by-step explanation:

The provided differential equation is a linear homogeneous second-order differential equation with constant coefficients. The general form of such an equation is given by
\(ay'' + by' + cy = 0\), where
\(ay'' + by' + cy = 0\)are constants. In this case, the coefficients are determined by the counts of letters in my first name
(\(f\)), middle name
(\(m\)), and last name
(\(l\)).

The characteristic equation associated with the given differential equation is obtained by substituting
\(y(x) = e^(rx)\) into the equation, resulting in
\(r^2 + (6 + 9f)r + (9l + 6m + 9) = 0\). Solving this quadratic equation yields two distinct roots
\(r_1\) and
\(r_2\).

Since the given solutions,
\(e^(-3x)\) and
\(xe^(-3x)\), are linearly independent, the general solution is expressed as a linear combination of these solutions, i.e.,
\(y(x) = c_1 e^(r_1x) + c_2 e^(r_2x)\). Substituting the roots into this form and simplifying, we obtain the final general solution
\(y(x) = c_1 e^(-3x) + c_2 x e^(-3x)\). The arbitrary constants
\(c_1\) and \(c_2\) are determined by any initial conditions or boundary values given for the specific problem at hand.

User Gisell
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