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VF.1 Vector Functions and Space Curves

In general, a function is a rule that assigns to each element in the domain an element in the range. A vector-valued function, or vector function, is simply a function whose domain is a set of real numbers and whose range is a set of vectors. This means for every number t in the domain of r there is a unique vector in 3-D space denoted by r(t). If $f(t),g(t)$, and $h(t)$ are the components of the vector r(t) , then f, g, and h are real valued functions called the component functions of r and we can write:


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The limit of a vector function r is defined by taking the limits of its component function as follows.

 

If MATH, then:


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Provided the limit of the component functions exist.


A vector function r is continuous at a if


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There is a close connection between continuous vector functions and space curves. Suppose that f, g, and h are continuous real-valued functions on an interval I. Then the set C of all points (x ,y ,z) in space, where


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and t varies throughout the interval I, is called a space curve. The equations in the part above are know as parametric equations of C and t is called a parameter.

 

 

 

 

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