Dividing by zero, zero divided by zero and zero to the power of zero - all pose problems! Numberphile on Facebook: www.facebook.com/numberphile Numberphile tweets: twitter.com/numberphile This video features Matt Parker and James Grime - twitter.com/standupmaths and twitter.com/jamesgrime Videos by Brady Haran A run-down of Brady's channels: periodicvideos.blogspot.co.uk/2012/06/here-are-my-channels.html