(Calc 3) Finding mass of a wire using line integral

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NWeid1
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Homework Statement


Find the mass of a wire in the shape of the parabola y=x2 for [itex]1 \leq x\leq2[/itex] and with density p(x,y)=x.

Homework Equations


The Attempt at a Solution



I just want to make sure I am setting this integral up right. Here is what I did:

I parameterized the equation to x=t, y=t2
and then got [itex]\int xds[/itex] from 1 to 2.
then I set ds = [itex]\sqrt{1+4t^2}*dt[/itex]

so I would have

[itex]\int t*\sqrt{1+4t^2}dt[/itex] from 1 to 2. Correct, or no?
 
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NWeid1 said:

Homework Statement


Find the mass of a wire in the shape of the parabola y=x2 for [itex]1 \leq x\leq2[/itex] and with density p(x,y)=x.

Homework Equations





The Attempt at a Solution



I just want to make sure I am setting this integral up right. Here is what I did:

I parameterized the equation to x=t, y=t2
and then got [itex]\int xds[/itex] from 1 to 2.
then I set ds = [itex]\sqrt{1+4t^2}*dt[/itex]

so I would have

[itex]\int t*\sqrt{1+4t^2}dt[/itex] from 1 to 2. Correct, or no?

Yes.