Definition of derivative integration problem

AI Thread Summary
The discussion revolves around an extra credit problem involving the derivative of an integral defined as G(x) = ∫[5 to x^2] √(1 + t^2) dt. Participants suggest using the definition of the derivative to find G'(x), referencing the formula for differentiating integrals with variable limits. There is a clarification regarding notation, emphasizing the distinction between the dummy variable and the final variable in the integral. A correction is made to improve clarity in the formula representation. The conversation highlights the importance of proper notation in calculus problems.
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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).
 
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Try going back to the definition of derivative.
 
The formula is
\int_{f(x)}^{g(x)} \phi (x)dx=\phi [g(x)]g'(x) - \phi [f(x)]f'(x)
 
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)
 
Oh Yes Thanks Halls for correcting
 
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