xy'=\int (-x)dx=>xy'=-\dfrac{x^2}{2}+C_1\\ y'=-\dfrac{x}{2}+\dfrac{C_1}{x}\\ y=\int(-\dfrac{x}{2}+\dfrac{C_1}{x})dx\\ y=-\dfrac{x^2}{4}+C_1lnx+C_2" alt="xy''+y'+x=0\\ xy''+y'=-x\\ (xy')'_x=-x=>xy'=\int (-x)dx=>xy'=-\dfrac{x^2}{2}+C_1\\ y'=-\dfrac{x}{2}+\dfrac{C_1}{x}\\ y=\int(-\dfrac{x}{2}+\dfrac{C_1}{x})dx\\ y=-\dfrac{x^2}{4}+C_1lnx+C_2" align="absmiddle" class="latex-formula">