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**Oneiromancy** Ok I have 2 problems that I can't do.

1) Find an equation in x and y whose graph is the path of the particle. Then find the particle's velocity and acceleration vectors at the given value of t.

**r**(t) = (t + 1)**i** + (t^2 - 1)**j** , t = 1

The answer is y = x^2 - 2x

I know how to get **v** and **a**.

2) Find parametric equations for the line that is tangent to the given curve at the given parameter value t_0 = 0

**r**(t) = (sin t)**i **+ (t^2 - cos t)**j **+ (e^t)**k **, t_0 = 0

The answer should be x = t , y = -1 , z = 1 + t

I thought all you do is find d**r**/dt then just plug in 0 but that didn't work.

These problems seem way too easy. I know I'm simply doing it completely wrong.