Khan/khan-exercises — Issue #12876: Domain of a function - Hint text is nonsensical.
Author: KhanBugz
Created: 2012-02-02 12:55:12+00:00
State: open
Labels: firefox, hard, xp

"The top radical is undefined when 6-x" is an incomplete sentence with no meaning.

"So the top radical is undefined when x>6, so we know x≤6." is a contradictory statement. Either we "know" that x is greater than 6, or we "know" that x is less than or equal to six. It can't be both.

"So the bottom radical is undefined when xA, so we know x≥1." The variable "A" has not been defined.

[domain_of_a_function.html?seed=114&problem=sqrt-frac](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/domain_of_a_function.html?seed=114&problem=sqrt-frac&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/domain_of_a_function.html?seed=114&problem=sqrt-frac&debug&activity=%5B%5B%22hint-activity%22%2C%220%22%2C673%5D%2C%5B%22hint-activity%22%2C%220%22%2C673%5D%2C%5B%22hint-activity%22%2C%220%22%2C674%5D%2C%5B%22hint-activity%22%2C%220%22%2C674%5D%2C%5B%22hint-activity%22%2C%220%22%2C674%5D%2C%5B%22hint-activity%22%2C%220%22%2C674%5D%2C%5B%22hint-activity%22%2C%220%22%2C674%5D%2C%5B%22hint-activity%22%2C%220%22%2C674%5D%2C%5B%22hint-activity%22%2C%220%22%2C675%5D%2C%5B%22hint-activity%22%2C%220%22%2C675%5D%5D)

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