How Do You Graph a Vector Function and Its Derivative?

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To graph the vector function and its derivative, the curve C is defined by the parametric equations x(t) = 2, y(t) = t, and z(t) = 4/(1+t^2). The user mistakenly attempted to set x, y, and z to zero, which is incorrect since x(t) is always 2. The correct approach involves recognizing that the curve lies in the plane x = 2, reducing the problem to plotting y(t) and z(t) against t. Clarification on the correct form of z(t) is also provided, emphasizing the importance of proper notation. Understanding these concepts is crucial for accurately graphing the vector function and its derivative.
p.ella
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Homework Statement


graph the curve C that is described by r and graph r′ at the indicated value of t.

I've attached the actual question as a picture as a picture file

Homework Equations



none

The Attempt at a Solution



I know x(t)= 2, y(t)=t , z(t)=4/1+t^2

when x=0, r(t)=t+4/1+t^2

when y=0, r(t)=2+4/1+t^2

when z=0, r(t)=2+t

Beyond this I have no idea what to do :( Any help would be very much appreciated, as this is quite urgent. Thank you in advance! (:
 

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p.ella said:

Homework Statement


graph the curve C that is described by r and graph r′ at the indicated value of t.

I've attached the actual question as a picture as a picture file


Homework Equations



none

The Attempt at a Solution



I know x(t)= 2, y(t)=t , z(t)=4/1+t^2

when x=0, r(t)=t+4/1+t^2

when y=0, r(t)=2+4/1+t^2

when z=0, r(t)=2+t

Beyond this I have no idea what to do :( Any help would be very much appreciated, as this is quite urgent. Thank you in advance! (:

Where do you get
z(t) = \frac{4}{1} + t^2 \, ?
I see
z(t) = \frac{4}{1+t^2}.
Did you mean z(t) = 4/(1+t^2), using parentheses to make it read properly?

Anyway, you are not allowed to set x = 0, because x(t) = 2 always. You are allowed to set y = 0, but only by setting t = 0 (because y(t) = t), etc. I cannot figure out what you are trying to do. The question asked you to plot ##\mathbf{r}(t)##, which is a curve in three dimensions; but since x = 2 always, it is really a plane-curve involving y and z, lying in the plane x = 2.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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