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**icelated** I have a parametrically defined curve where i am trying to find the second derivative.

here is the problem:

$\displaystyle x(t) = \frac {1}{t}$

and

$\displaystyle y(t) = -2 + lnt $

I need to find the equation for the tangent line to the curve at the point defined by t = 1

finding $\displaystyle \frac{dy}{dx}$

the dirivitive of x = $\displaystyle -\frac{1}{t^2}$

the dirivitive of y = $\displaystyle \frac{1}{t}$

then, i evaluate t = 1 by plugging it into

Sorry having some formatting issues below i hope you can read it..

$\displaystyle \frac{dy}{dt} \frac{1}{t}$

_______

$\displaystyle \frac{dx}{dt} \frac{-1}{t^2}$

after plugging in 1 for t

I get a slope of -1

so, then i need to take a second derivative

$\displaystyle \frac{d^2y}{dx^2} $

for the numerator its just 1

for the denominator its the derivative of x = $\displaystyle -\frac{1}{t^2}$

if so how do i evaluate that?