- #1
BrendanM
- 18
- 0
The question is : Find an F(x) where fprime(-1) = 1/2 , fprime(0) = 0 and fdoubleprime>0 if it doesn't exist prove why.
I cannnot explain it that well but here i go, i feel there is no equation that can be made for this. For an equation for be concave up on all intervals it must be in the form Ax^multipleof2 + B^multipleof2 + C^multipleof2 + etc etc etc... + Dx + E, where A and B and C... are positive constants I say this because f double prime will onyl be positive for all x if the second dirivitive has only positive constants or terms of x^multipleof2. Then the first dirivitive will leave you with x^odd number + a constant, f(-1) must be equal to 1/2, so it must be positive since x^oddnumber will be negative. but then when it says fprime(0) = 0 this cannot be because you will have 0^oddnubmer + constant.
blah that's as far as i could take it I am not sure if it makes sense.. but can someone help me on the correct path.
I cannnot explain it that well but here i go, i feel there is no equation that can be made for this. For an equation for be concave up on all intervals it must be in the form Ax^multipleof2 + B^multipleof2 + C^multipleof2 + etc etc etc... + Dx + E, where A and B and C... are positive constants I say this because f double prime will onyl be positive for all x if the second dirivitive has only positive constants or terms of x^multipleof2. Then the first dirivitive will leave you with x^odd number + a constant, f(-1) must be equal to 1/2, so it must be positive since x^oddnumber will be negative. but then when it says fprime(0) = 0 this cannot be because you will have 0^oddnubmer + constant.
blah that's as far as i could take it I am not sure if it makes sense.. but can someone help me on the correct path.
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