Calculate line integral.

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I have an example problem of a line integral below:

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It makes sense but the above problem is somewhat easy because the parametric equation is given to us.

I have this next problem:

  1. Calculate $\int_{C} F(r) \cdot dr$ for the given data.

$$F = [y^{2}, -x^{2}]$$

and C is a line from (0, 0) straight to (1, 4).

What is r(t)? CAn I say it's:

$$r(t) = [t, 4t]$$ $$r'(t) = [1, 4]$$ $$F(r(t)) = [16t^{2}, -t^{2}]$$

So the line integral is: $\int_0^1 [16t^{2}, -t^{2}] \cdot [1, 4]$

Is that right so far?

$$\int_0^1 [16t^{2} - 4t^{2}] $$ $$\int_0^1 [12t^{2}] $$

$$\left[4t^{3}\right]_0^1 = 4$$

Is that right?

Is the best way to interpret this the F's work done on something that is displaced along the straight line C by F's vectors along C?