Integral what has gone wrong here?

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I am still struggling my way through line integrals, and this here is one where I do not understand what has gone wrong - does anyone see what it is ( I really want to understand all of this)?

\int_{0}^{1}{(y*e^{xy} + 2x + y)dx + (x*e^{xy} + x )dy }

the curve joins (0,0) to (1,1)

where x= t and y=t (0<= t <= 1)

so, I said that

\frac {dx} {dt} = \frac {dy} {dt} = 1

therefore:
\int_{0}^{1} {( t*e^{t^2} + 2t + t + t*e^t^2 + t)dt} = \int_{0}^{1}{ (2t*e^{t^2} + 4t) dt} = e^1 + 1

However, the solution is supposed to be -2pi
 
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What do you mean by e^{t2}? Is it e^{2t} or e^{t^2}?

I guess it comes from the first expression, viz. ye^xy. Is it y^2e^x or ye^{xy}?

Never mind, going through your calculation, I can see what you meant.

Hmmm... I obtain the same thing as you. Are you sure about that parametrization?
 
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I am so sorry about that...I fixed it.

That's the parametrization the question stated:

(...) the curve joins (0,0) to (1,1)

where x= t and y=t (0<= t <= 1)

( I just double checked this)
 
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does it mabe help that the field is conservative?
 
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mmh37 said:
does it mabe help that the field is conservative?
A bit. That of course is the reason the path did not need to be given!

And it verifies that the correct answer is e+ 1.
 
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