Updates:
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Comment #12 on issue 2132 by mattpap: Derivative of RootSum
http://code.google.com/p/sympy/issues/detail?id=2132

All problems from #10 and #11 were fixed:

In [1]: a = S("(1-5*x^2)/(x-2*x^3+x^5-1)")

In [2]: a
Out[2]:
    ⎛       2⎞
   -⎝1 - 5⋅x ⎠
─────────────────
           3    5
1 - x + 2⋅x  - x

In [3]: b = integrate(a, x)

In [4]: b
Out[4]:
        ⎛ 5           ⎛        ⎛     2⎞⎞⎞
-RootSum⎝t  - t - 1, Λ⎝t, t⋅log⎝x - t ⎠⎠⎠

In [5]: b.diff(x)
Out[5]:
    ⎛       2⎞
   -⎝1 - 5⋅x ⎠
─────────────────
           3    5
1 - x + 2⋅x  - x

In [6]: RootSum(x**5 - x + 1, sin)
Out[6]:
       ⎛ 5                      ⎞
RootSum⎝x  - x + 1, Λ(x, sin(x))⎠

In [7]: _.doit()
Out[7]:
⎛ ⎛ 5 ⎞⎞ ⎛ ⎛ 5 ⎞⎞ ⎛ ⎛ 5 ⎞⎞ ⎛ ⎛ 5 sin⎝RootOf⎝x - x + 1, 0⎠⎠ + sin⎝RootOf⎝x - x + 1, 1⎠⎠ + sin⎝RootOf⎝x - x + 1, 2⎠⎠ + sin⎝RootOf⎝x - x + 1, 3

⎞⎞      ⎛      ⎛ 5           ⎞⎞
⎠⎠ + sin⎝RootOf⎝x  - x + 1, 4⎠⎠

In [8]: a = RootSum(z**5 - z**2 + 1, Lambda(z, z*log(x - z)))

In [9]: a.diff(x)
Out[9]:
 ⎛       2⎞
-⎝5 - 3⋅x ⎠
───────────
     2    5
1 - x  + x

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