MHB Multivariable calculus line integral work

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The discussion focuses on calculating the work done by the force field F(x,y) = (ye^{xy})i + (1 + xe^{xy})j along the curve defined by γ(t) = (2t - 1, t² - t) for t in [0,1]. The work is expressed as an integral involving the force field and the derivative of the curve. Participants also explore whether the force field is conservative and if a potential energy function V(x,y) exists that corresponds to F. The inquiry into the conservative nature of the force field suggests a deeper understanding of the relationship between work and potential energy. This analysis is crucial for applying concepts of multivariable calculus effectively.
kenporock
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calculate the work done by the force field $F(x,y)=(ye^{xy})i+(1+xe^{xy})j$ by moving a particle along the curve C described by
gamma (γ):[0,1] in $R^2$, where gamma (γ)=(2t-1, t²-t)
 
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kenporock said:
calculate the work done by the force field $F(x,y)=(ye^{xy})i+(1+xe^{xy})j$ by moving a particle along the curve C described by
gamma (γ):[0,1] in $R^2$, where gamma (γ)=(2t-1, t²-t)

Hi kenporock,

The work is:
$$\int_\gamma \mathbf F(\mathbf s)\cdot d\mathbf s = \int_\gamma \mathbf F(\boldsymbol\gamma(t)) \cdot d\boldsymbol\gamma(t) =
\int_0^1 \mathbf F(\boldsymbol\gamma(t))\cdot \boldsymbol\gamma'(t)\, dt$$

But before we go there, weren't you studying conservative force fields?
Is this one?
That is, can we find a potential energy function $V(x,y)$ such that $\mathbf F(x,y)=\pd V x \mathbf i + \pd V y \mathbf j$?
 
I am extremely grateful to you.
 
There are probably loads of proofs of this online, but I do not want to cheat. Here is my attempt: Convexity says that $$f(\lambda a + (1-\lambda)b) \leq \lambda f(a) + (1-\lambda) f(b)$$ $$f(b + \lambda(a-b)) \leq f(b) + \lambda (f(a) - f(b))$$ We know from the intermediate value theorem that there exists a ##c \in (b,a)## such that $$\frac{f(a) - f(b)}{a-b} = f'(c).$$ Hence $$f(b + \lambda(a-b)) \leq f(b) + \lambda (a - b) f'(c))$$ $$\frac{f(b + \lambda(a-b)) - f(b)}{\lambda(a-b)}...

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