C*x^2 + B*x - 4*C*x + A - 2*B + 2*C
[[A == 1, B == 3, C == 1]]
x^2 - x - 3
4*B2*x*cos(x) - 4*A2*x*sin(x) + 2*A2*cos(x) + 2*B1*cos(x) - 2*A1*sin(x) + 2*B2*sin(x)
[[A1 == 3, B1 == 2, A2 == 2, B2 == -1]]
-4*x*cos(x) + 8*x*sin(x) + 8*cos(x) - 8*sin(x)
[[u1p == -1, u2p == x*e^(-x)]]