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March 23rd, 2009, 06:39 AM
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| | kth derivative Let f(x)={x^n(1-x)^n}/n!. Then for any integer k>0, the kth derivatives f^(k)(0) and f^(k)(1)
A. are both 0 B. are both rational numbers but not necessarily integers
C. are both integers D. do not satisfy any of the foregoing properties
i was getting A as the answer but that is not right.. | 
March 23rd, 2009, 06:51 AM
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| | Quote:
Originally Posted by champrock i was getting A as the answer but that is not right.. | How did you arrive at your answer? What were your steps and reasoning?
Please be complete. Thank you! | 
March 23rd, 2009, 07:09 AM
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| | I just differentiated the function once and than twice and had put x=0, 1. The method I employed was more like a hit and trial method. It would be great if you could give a more systematic approach to the question. | 
March 23rd, 2009, 07:48 AM
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| | You could try finding more than just the first two derivatives... (Patterns sometimes take a while to "see".) | 
March 24th, 2009, 03:09 AM
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| | i did, but i was getting 0 only as the answer. Kindly help! | | Thread Tools | | | | Display Modes | Linear Mode |
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