- #1

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## Main Question or Discussion Point

A quick question. The fundamental theorem of calclus states that:

[tex] \frac{d}{dx} \int^x_a f(t)dt= f(x) [/tex]

I was wondering why the use of the dummy variable t, and not just x. Is it to distinguish that the function varies with the value t, and the limit of integration varies with a different variable x. I dont see what problem it would pose to call it f(x)dx.

[tex] \frac{d}{dx} \int^x_a f(t)dt= f(x) [/tex]

I was wondering why the use of the dummy variable t, and not just x. Is it to distinguish that the function varies with the value t, and the limit of integration varies with a different variable x. I dont see what problem it would pose to call it f(x)dx.