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For the homogeneous D.E. x2y′′−2xy′+(x2+2)y=0;y1​=xsin(x) and y2​=xcos(x) are both solutions.

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Final answer:

For the homogeneous differential equation
\(x^2y'' - 2xy' + (x^2 + 2)y = 0\), the solutions
\(y_1 = x\sin(x)\) and
\(y_2 = x\cos(x)\) are linearly independent solutions forming a fundamental set.

Step-by-step explanation:

The given differential equation is a second-order linear homogeneous differential equation with variable coefficients. The solutions
\(y_1\) and
\(y_2\) are both functions of x and satisfy the differential equation. To determine whether these solutions are linearly independent, we can use the Wronskian determinant.

The Wronskian determinant for two functions
\(y_1\) and
\(y_2\) is given by:


\[ W[y_1, y_2] = \begin{vmatrix} y_1 & y_2 \\ y_1' & y_2' \end{vmatrix} \]

Calculate the Wronskian determinant for
\(y_1 = x\sin(x)\) and
\(y_2 = x\cos(x)\). If
\(W \\eq 0\), then
\(y_1\) , and
\(y_2\) are linearly independent, forming a fundamental set of solutions for the homogeneous differential equation.

In this case, the Wronskian determinant is non-zero, indicating that
\(y_1 = x\sin(x)\) and
\(y_2 = x\cos(x)\) are linearly independent solutions. Therefore, they form a fundamental set of solutions for the given homogeneous differential equation. This is a crucial result in solving such equations, as it ensures the general solution can be expressed as a linear combination of these independent solutions.

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