Find the length of the curve from 0 to 1

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Homework Statement



find the length of the curve… r(t) = <4t, t^(2) + 1/6(t)^(3)> from 0≤t≤1

Homework Equations



L(t) = ∫a to b √(dx/dt)^(2) +(dy/dt)^(2) + (dz/dt)^(2))dt

The Attempt at a Solution



After taking the derivative of all components of the curve and finding the magnitude…
∫ 0 to 1 √(16+4t^(2) + 1/324(t)^(4))dt

And I can't manage to simplify any further.
I tried, doing ∫ 0 to 1 √(t)^(4) + 1296t^(2) + 5184

I don't know how to go any further in simplifying and pulling some t's out of the radical.
I know, it's some algebra, but I have no idea how to go about this from here.
 
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jorgegalvan93 said:
∫ 0 to 1 √(16+4t^(2) + 1/324(t)^(4))dt
The seem to be a few errors in the (dy/dt)2 term.
OTOH, corecting them makes the integrand look even worse.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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