I'm trying to evaluate arccot(0) but I can't find an approach that doesn't result in a divide by zero error. My math book seems to think it is possible (it says arccot(0) equals pi/2) but no matter how I try to evaluate it manually or on a calculator, it phails miserably. This is my procedure: Code: arccot 0 = ? cot ? = 0 tan ? = 1/0 EXCEPT YOU CAN'T EVALUATE 1/0!!!