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Homework Help: Finding the Tangent of a point on a curve (problem driving me crazy )

  1. Sep 11, 2008 #1
    1. The problem statement, all variables and given/known data
    I've done this problem about 5 times, several different ways following many different examples but I can't seem to find the right answer or even figure out how they got one of the answers (y answer is given)

    untitleddf.jpg


    3. The attempt at a solution

    r(t) = (1+4*sqrt(t), t5-t, t5+t)

    s(t) = P0 + tv (P and v are vectors)
    s(t) = r(0) + tr1(0)

    r1(t) = (2/sqrt(t), 5t4-1, 5t4+1)
    r1(0) = ????
    and this is where i get stuck because trying to substitute 0 in x equation will give you an undefined number...so i'm doing something wrong obviously...please help!!
     
  2. jcsd
  3. Sep 11, 2008 #2

    Dick

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    Science Advisor
    Homework Helper

    You want to find t such that (x,y,z)=(5,0,2). That's t=1, right? Why do you say t=0?
     
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