f(-x)=e^{2sec(-x)}ln\left( \frac{1-sinx}{1+sinx}\right)=-e^{2sec}ln\left( \frac{1+sinx}{1-sinx}\right)=-f(x)
f(x) is odd so :
for x>5 : f(x) = 1
\int_{-5}^{10}{f(x)dx}=\int_{-5}^{5}{f(x)dx}+\int_{5}^{10}{f(x)dx}
\int_{-5}^{10}{f(x)dx}=0+\int_{5}^{10}{1dx}
\int_{-5}^{10}{f(x)dx}=5