Question

求求学霸们帮我做一道题，我快被自己笨死了

求求学霸们帮我做一道题，我快被自己笨死了RT

Answer 1

let
u = y/(x+1)^2
du/dx = [1/(x+1)^2]. dy/dx - 2y/(x+1)^3
dy/dx =(x+1)^2. { du/dx + [2/(x+1)] u }
/
y' - [2/(x+1)]y =(x+1)^4
(x+1)^2. { du/dx + [2/(x+1)] u } - 2(x+1)u =(x+1)^4
(x+1)^2. du/dx =(x+1)^4
du/dx =(x+1)^2
u = ∫ (x+1)^2 dx
=(1/3)(x+1)^3 + C
y/(x+1)^2 = (1/3)(x+1)^3 + C
y =(1/3)(x+1)^5 + C(x+1)^2