Log in

No account? Create an account
brad's life [entries|archive|friends|userinfo]
Brad Fitzpatrick

[ website | bradfitz.com ]
[ userinfo | livejournal userinfo ]
[ archive | journal archive ]

Best CAPTCHA ever [Jul. 19th, 2007|10:52 am]
Brad Fitzpatrick
[Tags|, ]

A CAPTCHA gives you a little test to see if you're human, not a computer auto-generating accounts.

You know, this sort of crap:

But these guys have a way better one:


From: evan
2007-07-19 09:23 pm (UTC)

Re: Spelling it out ...

Alternatively, what I did was visualize what the derivatives at those well-known points are: the sin is maximally sloping upwards (+1) and the cos maximally downwards (-1), which got me to your second-to-last step without computing any derivatives directly. :)
(Reply) (Parent) (Thread)