# Tangent line to path

1. Sep 15, 2008

### rgalvan2

Find an equation for the line tangent to the given path at the indicated value for the parameter.

x(t)=4costi-3sintj+5tk, t=$$\pi$$/3

So what I did here was take x'(t) and then plugged in $$\pi$$/3 after that to get an equation containing i, j, and k.
x'(t)= -4sinti-3costj+5k
x'($$\pi$$/3)=-4$$\sqrt{3}$$/2i-3/2j+5k
Am I doing this right? Calc III is confusing me so much. Any help would be appreciated. This is due Thursday. Thanks!

2. Sep 15, 2008

### Dick

Looks all right so far.

3. Sep 15, 2008

### rgalvan2

Alright sweet thanks a lot!