## AllanaMaciel 2 years ago I need a help. Resolve the questions: a. (x^2 – y^2) dx + 2xydy = 0 b. y’ + (1/x)y = ex^2 c. y’’ + 2y’ + 2y = 0 d. y’’ – 3y’ + 2y = sen x e. (By Laplace transform) y’’ – y = 0, y(0) = 1, y’(0) = 1 f. { x’ = y {y’ = -2x +3y g. (by power series) y’ = y Usar a derivação termo a termo das séries 2. show that the series converges ∑ =1/n^2 when n=1 and tends to infinity converge

$\sum_{n=1}^{\infty} = 1/n^2$ converges