Question

a)Sketch the graph of the following parametric equations in xyz space. x=-t, y= 2cost, z= 3sint
b)Compute the point intersection of the tangent lines to the graph in (a) at the points A(0,2,0) and B(-pi/2,0,3)

Answer 1

Are you having problems with both of them? The first one, if you understand 3D graphing, all you have to do is pick a bunch of points t, perhaps from -3pi to 3pi with 1/4 pi changes, plug them into each part of the parametric.
For example, pi would ahve the coordinate (-pi, 0, 3)

Answer 2

t = pi*

Answer 3

For the tangent lines at a point, you just take the derivative of the point one part at a time (meaning the derivative of the x part, then the y part, then the z part). It's been a long time, so there's a chance I'm missing something here, but I don't believe there is.