x, y, P, Q, S, T = sympy.symbols('x y P Q S T')
c, y_0, y_c, dy_0, dy_c = sympy.symbols('c y_0 y_c dy_0 dy_c')
eq_y = P * x + Q + x * x * (S * x + T)
eq_dy = eq_y.diff(x)
equations = [(y_0 - eq_y).subs(x, 0), (dy_0 - eq_dy).subs(x, 0), (y_c -
    eq_y).subs(x, c), (dy_c - eq_dy).subs(x, c)]
solution_set = sympy.solve(equations, P, Q, S, T, set=True)
names = solution_set[0]
solutions = list(solution_set[1])
for k in range(len(solutions)):
    print('Solution #%d' % (k + 1))
for k2, name in enumerate(names):
    pass
Как решить нелинейное уравнение в Sympy?