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Given that x² y'+x y=1 . 1. Find a solution of the differential equation that satisfies the initial condition y(3)=6 . Answer: y=

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Final answer:

To solve the given differential equation with the initial condition y(3)=6, we find the integrating factor and integrate both sides. After applying the initial condition, we determine the constant of integration and arrive at the final solution for y.

Step-by-step explanation:

To find the solution of the given differential equation x² y' + x y = 1 that satisfies the initial condition y(3) = 6, we employ the method of separating variables or an integrating factor. However, since the provided information does not contain a clear method, we will proceed with the most likely applicable method given the first-order linear nature of the equation - using an integrating factor.

First, we rewrite the equation in the standard form for a linear first-order equation:

y' + \(\frac{1}{x}\)y = \(\frac{1}{x²}\)

The integrating factor \(\mu(x)\) is found by taking the exponential of the integral of \(\frac{1}{x}\):

\(\mu(x) = e^\int{\frac{1}{x} dx} = e^x = |x|\)

We multiply through by the integrating factor:

|x|y' + y = \(\frac{1}{x}\)

Now, we can notice that the left side of the equation is the derivative of |x|y. Thus, integrating both sides with respect to x:

\intx dx + \int{y dx} = \int{\frac{1}{x} dx}

|x|y = \ln|x| + C

Using the initial condition y(3) = 6, we can solve for the constant C:

3 \cdot 6 = \ln|3| + C

Therefore, C = 18 - \ln(3).

The solution is then given by:

y = \fracxx

Substituting back the value of C, we get:

y = \fracxx