Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Calc III help

  1. Feb 21, 2009 #1
    1. The problem statement, all variables and given/known data
    Given [tex]\vec{}[/tex]r"(t)= 6i-4cos (2t)j+ 9e3tk,
    r'[tex]\vec{}[/tex] (0)= 4i +3k and r[tex]\vec{}[/tex](0)=j+k, find r[tex]\vec{}[/tex](t).

    2. Relevant equations

    3. The attempt at a solution

    I will appreciate any ideas how to start this problem. Thank you.
  2. jcsd
  3. Feb 21, 2009 #2
    If r(t) = x(t)i + y(t)j + z(t)k, then r''(t) = x''(t)i + y''(t)j + z''(t)k.

    How you would you normally solve x''(t)=6 for x(t), given x'(0) and x(0) ?

    What is troubling you?
  4. Feb 21, 2009 #3
    I get it now. I need to integrate the given. Thank you.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook