问题描述: 求微分方程dy/dx+y/x=cosx的通解 1个回答 分类:数学 2014-12-03 问题解答: 我来补答 dy/dx + y/x = cosx积分因子 = e^∫ 1/x dx = e^ln|x| = x,乘以方程两边x · dy/dx + y = xcosxd(xy)/dx = xcosxxy = ∫ xcosx dxxy = ∫ x d(sinx) = xsinx - ∫ sinx dx = xsinx + cosx + Cy = sinx + (cosx)/x + C/x 展开全文阅读