Integrate f(t)f'(t) on [a,b] and Show 1/2[f''(b)-f''(a)]

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The discussion centers on the integration of the function f(t) multiplied by its derivative f'(t) over the interval [a,b]. Participants clarify that the correct expression involves f²(t) rather than f''(t) in the solution. The hint provided suggests calculating the derivative of F(x) = f''(x) to aid in the proof. There is a consensus that the original question may have been copied incorrectly, leading to confusion. The conversation emphasizes the importance of accurate transcription in mathematical problems.
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Let f be a function such that f' is continuous on [a,b]. Show that

\int_a^{b} f(t)f’(t) dt = 1/2 [f''(b) - f''(a)]

Hint: Calculate the derivative of F(x) = f''(x).
 
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Are you sure you copied the question correctly?
 
does it seem right now?
 
Shouldn't it be f² in the solution in stead of f" ?

i mean the integrand is f * df/dt * dt right? so you have f * df as integrand

marlon
 
1.DO NOT DOUBLE POST!

2.It's definitely
f^{2}(t)

The hint is good.I guess u needed us to tell u that u didn't copy the exercise properly. :-p

Daniel.
 
yes, you are right marlon, my bad all the way
 
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