6 Integrals to do. But shows error

@(r1,r2,theta1,theta2,z1,z2)-(r1.*r2.*(z1-z2))./((z1-z2).^2+r1.^2+r2.^2+r1.*r2.*cos(theta1-theta2)) This is my function. I have to integrate in 6 six-dimensions. integral, integral2, integral3 giving me error to start with. this is a constant error I am getting whichever function out of these three I use Q = integralCalc(fun,a,b,opstruct); I am trying to do numerical integration only.

please help