2/3 1 37 2 atan(------- + -------) sqrt(3) 5/6 21 3 %pi tan(----------------------- + ---) = 3 6 1/3 5/6 2/3 1/6 2 2 3 + 7 sqrt(3) + 27 2 3 --------------------------------------. 59 59?? Also, you may have wondered, along with me, if sometimes surd1(surd2(surd3)) can simplify to surd4(surd5), even though surd2(surd3) doesn't denest. To see that this can happen, just plug a generic surd3 for a into a symbolic denesting, such as 4 2 1/3 3 2 3 2 1/3 (a + (a + a) (3 a + 3 a + 3 a) - 3 a - 6 a - a) = 2 2/3 2 1/3 (a + a) - (a + a) + a. --rwg tetraodon detonator