Calculating Arc Length for r(t)=(10t^2,2*sqrt(10)*t, ln t) from t=1 to t=8

Larrytsai
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Homework Statement


Find the arclength of the curve r(t)=(10t^2,2*sqrt(10)*t, ln t)
for 1<=t<=8

Homework Equations





The Attempt at a Solution


i took the derivative of each component of vector r

20t,2sqrt(10),1/t
then i square each term and square root it

int sqrt( 400t + 40 + 1/t^2)dt

i can't integrate this to find out the length tho.
 
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Larrytsai said:

Homework Statement


Find the arclength of the curve r(t)=(10t^2,2*sqrt(10)*t, ln t)
for 1<=t<=8

Homework Equations





The Attempt at a Solution


i took the derivative of each component of vector r

20t,2sqrt(10),1/t
then i square each term and square root it

int sqrt( 400t + 40 + 1/t^2)dt
400t should be 400t2.
Larrytsai said:
i can't integrate this to find out the length tho.
If you make the change above, you'll have a perfect square that you can take the square root of.
 
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