Evaluate the definite integral of function dx/x^2+1 on interval [tan(3), tan(6)]
The Attempt at a Solution
The trigonometric inverse function for dx/x^2+1 is arctanx+c.
I plugged in tan(3) and tan(6), and subtracted arctan(tan(3)) from arctan(tan(6)) and got the answer -.1415. But it's incorrect...
What am I doing wrong?