>> syms x;
>> int(1/(cos(x))^(1/2))
ans =
-2*(-(2*cos(1/2*x)^2-1)*(-1+cos(1/2*x)^2))^(1/2)*(1-cos(1/2*x)^2)^(1/2)*(-2*cos(1/2*x)^2+1)^(1/2)/(-1-2*cos(1/2*x)^4+3*cos(1/2*x)^2)^(1/2)*EllipticF(cos(1/2*x),2^(1/2))/sin(1/2*x)/(2*cos(1/2*x)^2-1)^(1/2)
这是借用matlab求解出来的结果,复杂吧!估计不会有耐心手算出来的