Sketch Vector Functions: r(t), r'(t) for t=1

  • Thread starter Thread starter Physicsnoob90
  • Start date Start date
  • Tags Tags
    Functions Vector
Physicsnoob90
Messages
51
Reaction score
0

Homework Statement


(a) Sketch the plane with the given vector expression
(b) find r'(t)
(c) sketch the position vector r(t) and the tangent vector r'(t) for the given value of t

r(t) = <t^2,t^3> t=1

Homework Equations





The Attempt at a Solution


1) i derived the equation : r'(t) = <2t,3t^2>
2) sub in t=1: r(t)=<1,1>
r'(t)=<2,3>

I've always been a terrible graphing person so if anyone can help me improve on this, it would be really helpful
 
Physics news on Phys.org
Please show your working and reasoning.
 
Do you understand that, in the xy-plane, r= <t^2, t^3> covers the same curve as x= t^2, y= t^3? Have you just calculated a number of (x, y) points for different t to help in drawing the curve? For example when t= 0, x and y are both 0 so (0, 0) is a point on the curve. When t= 1 the point is (1, 1). When t= -1, (1, -1), when t= 2, (4, 8), when t= 1/2, (1/4, 1/8), etc.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
Back
Top