My Math Forum Find the tangent line approximation

 Calculus Calculus Math Forum

 March 19th, 2017, 06:43 PM #1 Member   Joined: Feb 2017 From: henderson Posts: 36 Thanks: 0 Find the tangent line approximation Find the tangent line approximation for f(x) = 1/x near x=8 so I used the f(a) +f'(a)(x-a) f = 1/x f' = -1/x^2 I end up writing y - 1/8 = -1/64 (x + 8) my answer I get is -1/64 - 1/4, but it's wrong so I am stuck. :/ Any help? Last edited by skipjack; March 19th, 2017 at 11:12 PM.
 March 19th, 2017, 07:15 PM #2 Senior Member     Joined: Sep 2015 From: USA Posts: 2,533 Thanks: 1390 $f(x)=\dfrac 1 x$ $f'(x) = -\dfrac{1}{x^2}$ $f(8) = \dfrac 1 8$ $f'(8) = -\dfrac{1}{64}$ $f(x) \approx \dfrac 1 8 - \dfrac {1}{64}\left(x - 8\right) = -\dfrac{1}{64}x +\dfrac 1 4$ you're trying to produce a function of $x$, not a number.

 Tags approximation, find, line, tangent

 Thread Tools Display Modes Linear Mode

 Similar Threads Thread Thread Starter Forum Replies Last Post noobinmath Pre-Calculus 4 March 23rd, 2016 10:31 AM DerGiLLster Calculus 1 October 20th, 2015 07:04 PM Shamieh Calculus 2 October 7th, 2013 05:12 AM Shamieh Calculus 3 September 23rd, 2013 02:16 PM SSmokinCamaro Calculus 2 March 1st, 2009 12:54 PM

 Contact - Home - Forums - Cryptocurrency Forum - Top