Hi guys, I am trying to integrate the following expression: u_ratio:=(4/omega_star)*(sin(omega*t)-(exp(-B)/sqrt(r_star))*sin(omega*t-B)); where omega_star:=omega*r0^2/nu; r_star:=r/r0; B:=(1-r_star)*(sqrt(omega_star/2)); I would like to obtain integral of u_ratio with respect to r_star, and separately the integral of u_ratio over one period. When i try to use something like int(u_ratio,r_star) in only get back a large expression with an integral symbol still in it. What would be the best way to approach integrating this guy? Thanks, Randy