xy''-(x+1)y'+y=0
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MathBot Answer:
\[y{\left(x \right)} = \left(1 + x\right) C_{2} + x^{2} \left(1 + \frac{x}{3} + \frac{x^{2}}{12} + \frac{x^{3}}{60}\right) C_{1} + O\left(x^{6}\right)\]
\(C_{1}\), \(C_{2}\) are arbitrary constants.
\(O\) is the error term of the series expansion in big O notation. The error term describes the maximum size of the error near \(x = 0\) between the exact solution \(y{\left(x \right)}\), and the approximate solution \(x^{2} C_{1} \left(\frac{x^{3}}{60} + \frac{x^{2}}{12} + \frac{x}{3} + 1\right) + C_{2} \left(x + 1\right)\). \(y{\left(x \right)} = C_{2} \left(x + 1\right) + x^{2} C_{1} \left(\frac{x^{3}}{60} + \frac{x^{2}}{12} + \frac{x}{3} + 1\right) + O\left(x^{6}\right)\) means that there exists a positive constant \(M\) such that for \(x\) sufficiently close to zero \(|y{\left(x \right)} - \left(\left(1 + x\right) C_{2} + x^{2} \left(1 + \frac{x}{3} + \frac{x^{2}}{12} + \frac{x^{3}}{60}\right) C_{1}\right)| \le M |x^{6}|\).