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tandoorichicken
Jan13-04, 07:20 PM
This was an extra credit problem on our last test. We haven't learned how to do it yet but I was just curious as to how it would be done.

\int^{x^2}_{5} \sqrt{1 + t^2} \,dt = G(x)
Find G'(x).

Hurkyl
Jan13-04, 09:15 PM
Try going back to the definition of derivative.

himanshu121
Jan14-04, 01:38 AM
The formula is
\int_{f(x)}^{g(x)} \phi (x)dx=\phi [g(x)]g'(x) - \phi [f(x)]f'(x)

HallsofIvy
Jan14-04, 05:40 AM
himanshu121, that's an unfortunate notation. It's difficult to distinguish where x is the "dummy" variable and where it is the final variable.

Better would be:
\int_{f(x)}^{g(x)} \phi (t)dt=\phi [g(x)]g'(x) - \phi [f(x)]f'(x)

himanshu121
Jan14-04, 05:52 AM
Oh Yes Thanks Halls for correcting