Y = y₁ + y₂
решаем общее однородное
y" + y' = 0
l² + l = 0
l(l + 1) = 0
l₁ = 0
l₂ = -1
y₁ = С₁ + С₂e^{-x}
y₂ = Ax³ + Bx² + Cx
6Ax + 2B + 3Ax² + 2Bx + C = 49 - 24x²
3A = -24 => A = -8
6A + 2B = 0
-48 + 2B = 0
B = 24
2B + C = 49
C = 1
y₂ = -8x³ + 24x² + x
y = C₁ + C²e^{-x} - 8x³ + 24x² + x - общее решение