• earned_myself_a_gin@reddthat.com
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    1 year ago

    Can someone explain this? Integral from 10 to 13 of 2x? It’s been a long time since calculus for me, but isn’t that like 2x² + c or something like that?

    • CelloMike@startrek.website
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      1 year ago

      Just x²+c, but when you’re integrating between limits the +c doesn’t matter - so you’re just left with the difference between 13² and 10²…

      • T (they/she)@beehaw.org
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        1 year ago

        It isn’t that it doesn’t matter, constant of integration is only used for indefinite integrals.

        • qjkxbmwvz@lemmy.sdf.org
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          1 year ago

          I think it’s “indefinite” not “undefined” (at least in English).

          The reason it doesn’t matter/is only used for indefinite integrals is just that it gets subtracted out when you evaluate at the limits of integration, so it always goes away (but it’s still there in the antiderivative).

          (x1+c)-(x0+c) = x1-x0

          • T (they/she)@beehaw.org
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            1 year ago

            I think it’s “indefinite” not “undefined” (at least in English).

            You are correct, it has been at least ten years since my calculus classes which I took in a language that isn’t English.

    • zigmus64@lemmy.world
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      1 year ago

      The integral of 2xdx is x^2 + c, and it’s evaluated from 10 to 13. So you’d have the following:

      (13^2 + c) - (10^2 + c).

      The c’s cancel. I’ll leave you to do the rest…