Difference between 2009B and 2012B

Hi everybody! I have recognised today that the definite integration of an equation 1/(1+6(sin(x))^2) on (0,2pi) is different in 2009B and 2012B. In 2009B, the answer is (pi7^(1/2)/7) whereas (2pi7^(1/2))/7 in 2012B. What is the right answer? Why the answer is different in each other?

I have to say that, I also find this integral's answer (2pi7^(1/2))/7 by the Residue theorem, by hand. Thanks for helping and your interest.

BIRD, Istanbul Tech. Uni.