Question: Calculating Work with a Line Integral

Breedlove
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Homework Statement


Find the work doneby the force field F on a particle that moves along the curve C.
F(x,y)=xy i + x^2j
C: x=y^2 from (0,0) to (1,1)


Homework Equations



\intF dot dr=\int^{b}_{a}F(r(t))dotr'(t)dt

The Attempt at a Solution



Okay, so I parametrized x=t and y=t^2 (giving r(t)=ti+t^2j right?) and substituted those values in for x and y in F, dotted that with 1i+2tj because I think that it is the derivative of r, if the parametric equations for r are x=t and y=t^2. I then took the integral of the dot product i just took over the interval 0 to 1. I ended up with 3/4 but the correct answer is 3/5
 
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Breedlove said:
Okay, so I parametrized x=t and y=t^2 (giving r(t)=ti+t^2j right?)
No, the curve is x=y^2 not y=x^2 so your parametric form of y should be y=\sqrt{t}. Alternatively use: y=t and x=t^2.
 
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...
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