Let the left and right focus of ellipse C: x ^ 2 / A ^ 2 + y ^ 2 / b ^ 2 = 1 (a > b > 0) be F1, F2, p be the point PF2 ⊥ F1F2 on C, and the angle pf1f2 = 30 °, then the eccentricity of C is

In the △ f1pf2, in the ififf1f2 | / | Pf1 | Pf1 | / ifififif1 | / ififif2

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