Need help solving a differential equation

lilmul123
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Homework Statement



dy/dx = 2y + x^2 + 5.

This is a linear differential equation, so I know I need to use the definition of it which is y*e^integral(P(x)) dx = integral(f(x)*e^int(P(x)) dx.


I tried to get it into this form, so I tried to change the equation to dy/dx + -2y = x^2 + 5. Eventually, the right side of my linear equation for solving becomes the integral of (x^2 + 5)*e^-2x dx. The 5e^-2x dx is easy to integrate, but x^2*e^-2x dx is not. Did I form my initial equation correctly or am I really supposed to find the integral of that?
 
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Use integration by parts twice to integrate x2e-2x.
 
Yeah, I figured it out after looking at it for a while. Thank you.
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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