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Question about vectors and dot product.

  1. Dec 30, 2009 #1
    Can someone tell me if: -E dotted with ( A + B )

    is equal to -E.A -E.B where E, A and B are all vectors

    What I mean is, does the minus sign appear on the E.B bit as well?

    Also, is [tex]\int \frac{d}{dt} (A) dV[/tex]

    equal to: [tex]\frac{d}{dt} \int (A) dV[/tex]

    Thank you
  2. jcsd
  3. Dec 30, 2009 #2
    1) Yes off course.

    2) Usually the conditions are for all to be "nice": A must be differentiable wrt to t at every point in V, the former integral must converge in order for it to be equal to the latter. I guess you are working with such a "nice" field and volume V, so in that case you may switch differentiation and integration.
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