Uh oh! Wolfram|Alpha doesn't run without JavaScript.
Please enable JavaScript. If you don't know how, you can find instructions
here
.
Once you've done that, refresh this page to start using Wolfram|Alpha.
arccos ((1500*600+1*1)/(sqrt((1500^2+1^2)*(600^2+1^2))))
arccos ((1500*600+1*1)/(sqrt((1500^2+1^2)*(600^2+1^2))))
Natural Language
Math Input
Extended Keyboard