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Let us consider a curve, $$y = f(x)$$ passing through the point $$(-2, 2)$$ and the slope of the tangent to the curve at any point $$(x, f(x))$$ is given by $$f(x) + xf'(x) = x^2$$. Then
We are told that the curve satisfies the differential relation $$f(x)+x\,f'(x)=x^{2}.$$
First, we rewrite it so that the coefficient of $$f'(x)$$ is 1. Dividing every term by $$x$$ (we assume $$x\neq 0$$ while differentiating), we obtain
$$f'(x)+\frac{1}{x}\,f(x)=x.$$
This is a linear first-order differential equation of the standard form
$$y'+P(x)\,y=Q(x),$$
where here $$y=f(x),\; P(x)=\dfrac{1}{x},\; Q(x)=x.$$
For such an equation, the integrating factor is defined by
$$\mu(x)=e^{\int P(x)\,dx}.$$
We calculate the integral of $$P(x):$$
$$\int \frac{1}{x}\,dx=\ln|x|.$$
Hence
$$\mu(x)=e^{\ln|x|}=|x|.$$
For simplicity we take $$\mu(x)=x$$ (the sign has no effect on the integration that follows). Multiplying the entire differential equation by this integrating factor, we get
$$x\,f'(x)+f(x)=x^{2}.$$
Now observe that the left‐hand side is precisely the derivative of the product $$x\,f(x)$$ with respect to $$x$$, since
$$\frac{d}{dx}\bigl[x\,f(x)\bigr]=x\,f'(x)+f(x).$$
Therefore the differential equation reduces to the very simple form
$$\frac{d}{dx}\,[x\,f(x)]=x^{2}.$$
We integrate both sides with respect to $$x$$:
$$x\,f(x)=\int x^{2}\,dx=\frac{x^{3}}{3}+C,$$
where $$C$$ is the constant of integration. Solving for $$f(x)$$ gives
$$f(x)=\frac{x^{2}}{3}+\frac{C}{x}.$$
The curve passes through the point $$(-2,\,2)$$, so we substitute $$x=-2$$ and $$f(x)=2$$ to find $$C$$:
$$2=\frac{(-2)^{2}}{3}+\frac{C}{-2}=\frac{4}{3}-\frac{C}{2}.$$
Clearing denominators by multiplying every term by $$6$$:
$$12=8-3C.$$
Thus
$$3C=-4\;\Longrightarrow\;C=-\frac{4}{3}.$$
We now insert this value back into the expression for $$f(x)$$:
$$f(x)=\frac{x^{2}}{3}-\frac{4}{3x}.$$
To eliminate the denominators, multiply both sides by $$3$$:
$$3\,f(x)=x^{2}-\frac{4}{x}.$$
Next multiply every term by $$x$$ to remove the remaining fraction:
$$3x\,f(x)=x^{3}-4.$$
Finally, bring all terms to one side to obtain a purely algebraic relation between $$x$$ and $$f(x)$$:
$$x^{3}-3x\,f(x)-4=0.$$
This matches the expression given in Option A. None of the other options coincide with the derived relation.
Hence, the correct answer is Option A.
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