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.
Implies(Implies(p,Implies(q,r)), Implies(Implies(p,~r),Implies(p,~q)))/
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random
