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* ((d * 2) / m - 1) * ((d * 2) / m - 1) + 1) * (m / c)
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random