Originally Posted by

**saxyliz** Here's the problem:

Find parametric equations for the tangent line to the curve with the given parametric equations at the specified point:

$\displaystyle x = e^-t * cos(t)$

$\displaystyle y = e^-t * sin(t)$

$\displaystyle z = e^-t$

At the point: (1,0,1)

(It's supposed to be e to the negative t, I just can't get the math software to work properly).

I know the answer is supposed to be:

$\displaystyle x = 1-t$

$\displaystyle y = t$

$\displaystyle z = 1-t$

but I have no idea how to get there! Help!