Solve x log x·y′+y=(2/x)log x, with the original real-log domain x>0.
💡 Concept Hints
Identify the domain and the inner and outer functions, or the relevant one-sided limits.
Apply the appropriate differentiation or limit rule, keep all chain factors, and check exceptional points.
✅ Step-by-Step Solution
Final Answer: y = \(\frac{C x - 2 \log{\left(x \right)} - 2}{x \log{\left(x \right)}}\), for x>0, x≠1; use the undivided equation to examine any possible extension at 1.
Write y′ + \(\frac{1}{x \log{\left(x \right)}}\) y = \(\frac{2}{x^{2}}\); work for x>0, x≠1; use the undivided equation to examine any possible extension at 1.
An integrating factor is μ=\(\log{\left(x \right)}\), since μ′/μ=\(\frac{1}{x \log{\left(x \right)}}\).
Integrate the right side: \(\frac{- 2 \log{\left(x \right)} - 2}{x}\). Thus μy=\(\frac{- 2 \log{\left(x \right)} - 2}{x}\)+C.
Therefore y = \(\frac{C x - 2 \log{\left(x \right)} - 2}{x \log{\left(x \right)}}\).
At x=1 the undivided equation requires y(1)=0. Only C=2 has a removable singularity in the displayed family; it extends with y(1)=0 and y′(1)=1. Other constants cannot give a finite solution there.
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