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Let $$y = y(x)$$ be the solution of the differential equation, $$xy' - y = x^2(x\cos x + \sin x)$$, $$x > 0$$. If $$y(\pi) = \pi$$, then $$y''\left(\frac{\pi}{2}\right) + y\left(\frac{\pi}{2}\right)$$ is equal to:
We start from the given differential equation
$$x\,y' \;-\; y \;=\; x^{2}\bigl(x\cos x + \sin x\bigr), \qquad x > 0.$$
Because a factor of $$x$$ is multiplying $$y'$$, we first divide the whole equation by $$x$$ (allowed since $$x > 0$$) so that the derivative term stands alone:
$$y' \;-\; \frac{1}{x}\,y \;=\; x^{2}\cos x \;+\; x\sin x.$$
This is a first-order linear differential equation of the standard form
$$y' + P(x)\,y = Q(x),$$
with
$$P(x) = -\frac{1}{x}, \qquad Q(x) = x^{2}\cos x + x\sin x.$$
The integrating factor is obtained from the formula $$\mu(x)=e^{\int P(x)\,dx}.$$ Hence
$$\mu(x)=\exp\!\bigl(\int -\tfrac{1}{x}\,dx\bigr) =\exp(-\ln x)=x^{-1}.$$
Multiplying every term of the differential equation by this integrating factor $$x^{-1}$$ gives
$$x^{-1}y' \;-\;x^{-2}y \;=\;x^{-1}\!\bigl(x^{2}\cos x + x\sin x\bigr) \;=\;x\cos x + \sin x.$$
By construction the left-hand side is the exact derivative of $$\mu(x)y=x^{-1}y$$:
$$\frac{d}{dx}\!\bigl(x^{-1}y\bigr) \;=\; x\cos x + \sin x.$$
We now integrate both sides with respect to $$x$$:
$$x^{-1}y \;=\; \int \bigl(x\cos x + \sin x\bigr)\,dx + C.$$
We evaluate the integral term by term.
First, for $$\displaystyle\int x\cos x\,dx$$ we apply integration by parts:
Let $$u = x \;\Rightarrow\; du = dx,$$ and $$dv=\cos x\,dx \;\Rightarrow\; v=\sin x.$$ Then
$$\int x\cos x\,dx = x\sin x -\!\int\!\sin x\,dx = x\sin x + \cos x.$$
Second, $$\displaystyle\int \sin x\,dx = -\cos x.$$
Adding the two results, the sum of the integrals is simply
$$x\sin x + \cos x \;+\;(-\cos x)=x\sin x.$$
Thus we have
$$x^{-1}y = x\sin x + C.$$
Multiplying through by $$x$$ gives the explicit solution
$$y(x)=x^{2}\sin x + Cx.$$
We next use the initial condition $$y(\pi)=\pi$$ to find the constant $$C$$:
$$\pi = y(\pi)=\pi^{2}\sin\pi + C\pi = 0 + C\pi,$$
so $$C = 1.$$ Substituting this back, our solution becomes
$$y(x)=x^{2}\sin x + x.$$
Now we need $$y''\!\bigl(\tfrac{\pi}{2}\bigr)+y\!\bigl(\tfrac{\pi}{2}\bigr).$$ To do this we first differentiate $$y(x)$$ twice.
The first derivative :
$$\begin{aligned} y'(x) &= \frac{d}{dx}\bigl(x^{2}\sin x + x\bigr) \\ &= 2x\sin x + x^{2}\cos x + 1. \end{aligned}$$
The second derivative :
$$\begin{aligned} y''(x) &= \frac{d}{dx}\bigl(2x\sin x + x^{2}\cos x + 1\bigr) \\ &= 2\sin x + 2x\cos x + 2x\cos x - x^{2}\sin x \\ &= 2\sin x + 4x\cos x - x^{2}\sin x. \end{aligned}$$
We now evaluate these expressions at $$x = \dfrac{\pi}{2}.$$
Noting that $$\sin\!\bigl(\tfrac{\pi}{2}\bigr)=1$$ and $$\cos\!\bigl(\tfrac{\pi}{2}\bigr)=0,$$ we have
$$\begin{aligned} y''\!\bigl(\tfrac{\pi}{2}\bigr) &= 2\cdot 1 \;+\; 4\cdot \tfrac{\pi}{2}\cdot 0 \;-\;\bigl(\tfrac{\pi}{2}\bigr)^{2}\cdot 1 \\ &= 2 - \frac{\pi^{2}}{4}. \end{aligned}$$
Similarly,
$$\begin{aligned} y\!\bigl(\tfrac{\pi}{2}\bigr) &= \bigl(\tfrac{\pi}{2}\bigr)^{2}\!\cdot 1 \;+\;\tfrac{\pi}{2} = \frac{\pi^{2}}{4} + \frac{\pi}{2}. \end{aligned}$$
Adding these two values gives
$$\begin{aligned} y''\!\bigl(\tfrac{\pi}{2}\bigr) + y\!\bigl(\tfrac{\pi}{2}\bigr) &= \Bigl(2 - \frac{\pi^{2}}{4}\Bigr) + \Bigl(\frac{\pi^{2}}{4} + \frac{\pi}{2}\Bigr) \\ &= 2 + \frac{\pi}{2}. \end{aligned}$$
Hence, the correct answer is Option A.
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