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.
norm of (a, b, 0) cross (c, d, 0)
norm of (a, b, 0) cross (c, d, 0)
Natural Language
Math Input
Extended Keyboard