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Higher derivative product rule second degree differentiation (1 Viewer)

Thatstudentm9

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Hey guys I was doing this question in the following methods:

question: find d^2v/dt^2 if v=(t+3)(2t-1)2

1) u=t+3 u'=1 and v=(2t-1)^2 v'=4(2t-1)

2) sub in the values obtained into u'v+v'u ................................ =1(2t-1)^2+4(2t-1)(t+3)

3) (from this point on i was somewhat confused whether to expand and then factorise or just jump st8 into factorization)

this btw the first degree differentiation moviand reng of to the second. I know this is a long question requires heaps of working out but can someone please help me with this question as i saw it in a past paper and csa trial paper. Your help would be highly appreciated
 

InteGrand

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Hey guys I was doing this question in the following methods:

question: find d^2v/dt^2 if v=(t+3)(2t-1)2

1) u=t+3 u'=1 and v=(2t-1)^2 v'=4(2t-1)

2) sub in the values obtained into u'v+v'u ................................ =1(2t-1)^2+4(2t-1)(t+3)

3) (from this point on i was somewhat confused whether to expand and then factorise or just jump st8 into factorization)

this btw the first degree differentiation moviand reng of to the second. I know this is a long question requires heaps of working out but can someone please help me with this question as i saw it in a past paper and csa trial paper. Your help would be highly appreciated
 
Last edited:

jjHasm

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Hey guys I was doing this question in the following methods:

question: find d^2v/dt^2 if v=(t+3)(2t-1)2

1) u=t+3 u'=1 and v=(2t-1)^2 v'=4(2t-1)

2) sub in the values obtained into u'v+v'u ................................ =1(2t-1)^2+4(2t-1)(t+3)

3) (from this point on i was somewhat confused whether to expand and then factorise or just jump st8 into factorization)

this btw the first degree differentiation moviand reng of to the second. I know this is a long question requires heaps of working out but can someone please help me with this question as i saw it in a past paper and csa trial paper. Your help would be highly appreciated
im assuming theres a little typo and that v is meant to = (t+3)(2t-1)^2. If the way InteGrand mentioned seems too confusing, just expand everything and differentiate v 2 times, so u wont have to worry about product rule. Just simple differentation, no brackets. I believe it should be 24t+16 ? All InteGrand is doing I believe is using product rule 2 times?

Either this or im retarded and don't know what the question is asking for :p
 
Last edited:

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