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

Tangent line of a line

  1. May 1, 2010 #1
    We know that the slope of the tangent line at a point on a curve is found by evaluating the derivative of the curve at that point.

    Say we have the curve y=2x.
    Say I wanted to find the tangent line at x=4
    dy/dx=2
    The first derivative is a constant, which is not surprising since the curve is always changing at the same rate.
    However, since the first derivative is a constant, how can I find the equation of the tangent line at x=4? We can't say it's y=2 since that line does not intersect y=2x at x=4.

    Can anyone help me
     
  2. jcsd
  3. May 1, 2010 #2

    Integral

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    The tangent to a line is the line itself.
     
  4. May 1, 2010 #3
    Ohhh I forgot you needed to multipliy the slope by x. Thank you very much
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Tangent line of a line
  1. Tangent Line (Replies: 2)

  2. Tangent line (Replies: 7)

  3. Find a tangent line? (Replies: 7)

  4. Tangent Line (Replies: 4)

Loading...