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.
1/ ((sin (pi/7))^2) +1/ ((sin (2pi/7))^2) +1/ ((sin(4pi/7))^2)
1/ ((sin (pi/7))^2) +1/ ((sin (2pi/7))^2) +1/ ((sin(4pi/7))^2)
Natural Language
Math Input
Extended Keyboard
