Finding a Vector-Valued Function to Parametrize the Curve (x-1)^2 + y^2 = 1

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The discussion focuses on finding a vector-valued function to parametrize the curve defined by the equation (x-1)^2 + y^2 = 1, which represents a circle centered at (1,0). The proposed parametrization is x(t) = cos(t) + 1 and y(t) = sin(t), leading to the vector-valued function r(t) = (cos(t) + 1)i + sin(t)j. Participants confirm that this is a correct parametrization and emphasize the importance of visualization in the process. They note that while there are many possible parameterizations, some methods may be more intuitive or suitable depending on the context, and there is no universal algorithm for all parametrization problems.
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Homework Statement



Find a vector-valued function f that parametrizes the curve (x-1)^2 + y^2 = 1

Homework Equations



(x-1)^2 + y^2 = 1

The Attempt at a Solution



The equation is the graph of a circle that is 1 unit to the right of the origin, therefore a parametrization would be

x(t) = cos(t) + 1
y(t) = sin(t)

Therefore a vector-valued function that parametrizes this curve is given by

r(t) = (cos(t) + 1)i + sin(t)jI've been having trouble with parametrization lately so I was wondering if this is correct. Also, is there a better method to go about this sort of thing? Is it entirely visual and you just have to have a "feel" for it?
 
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Yes, that would be a correct parametrisation. There are of course ways to check that it is correct.
 
CAF123 said:
Yes, that would be a correct parametrisation. There are of course ways to check that it is correct.

But is there an algorithm or anything to go about it? I just had to visualize it. Will every parametrization problem be like that?
 
cytochrome said:
But is there an algorithm or anything to go about it? I just had to visualize it. Will every parametrization problem be like that?

I would say pretty much yes to that. There are always many possible parameterizations and often some are more natural or "better" than others for a particular purpose. In your example, visualizing it as a circle and thinking in terms of sines and cosines is exactly the appropriate approach. There isn't a magic procedure that will always mindlessly work.
 
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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