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It is well known that:

$$\frac{\Gamma(c)}{\Gamma(a) \Gamma(c-a)} \int_0^1 du \, \frac{u^{a-1}(1-u)^{c-a-1}}{(1-ux)^{b_1} (1-uy)^{b_2}} = \mathfrak{F} \, (a; b_1, b_2; c \, | \, x, y) = \\ =\sum_{n = 0}^{\infty} \frac{(a)_n}{(c)_n} \sum_{n_1 + n_2 = n} (b_1)_{n_1} (b_2)_{n_2} \frac{x^{n_1}}{n_1!} \frac{y^{n_2}}{n_2!}$$

where $\mathfrak{F}$ is the (first) Appell function.

Whence one is able to express:

$$\int_0^1 du \, \frac{u^{a-1}(1-u)^{b-1}}{(u^2 A - u(1-u) B + (1-u)^2 C)^{c}}$$

through $\mathfrak{F}$'s, however, the obtained expression isn't very pleasant. On this account, I'd like to ask whether there is a "nice" formula for the above integral (in terms of hypergeometric functions)?

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    I take it you didn't want to factor the denominator? Extract/add terms to form (1-ux)^c(1-u*y)^c ? The x,y are defined in the factoring/extracting step. – rrogers May 05 '18 at 21:18

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